Ice water hash – a complete guide from harvest to dab

The amazing title picture was taken by the one and only Even Stone. Follow him on Instagram!

What is water-hash?

As you probably already expected from the heading for this method of separating trichomes from cannabis flower, we use a combination of ice and water. This mechanical procedure uses the force of the water vortex to brush of the oleoresin containing trichomeheads from yours buds. The ice in ice-water-hash making is only used to cool the whole mix down in order to make the stalks of the trichomes brittle so that they break of more easily. But the exact steps you need to take and much more will be discussed in the following article.

Why choose water-hash?

When you hear about ice-water-hash most times it sounds pretty labourintensive and it is, but the ratio of quality per worktime is the highest of the different solventless methods. Dry-ice-sifting for example oxidises the trichomes so fast that they burst and leaks out the desired compounds like the really volatile monoterpenes (limonene). And not only the trichomes burst, the plant material gets also really brittle, really fast so the contamination rate also increases rapidly. This results in a drastic loss of quality and worth, because even when pressed this can only achieve low prices on the market.

Dryice-Hash with a lot of Contaminants
Badly contaminated, green dry ice sift from GrowWeedEasy

Then why not use drysift, there’s no dry ice used and no enhanced oxidation. Thats completely true, but as we’re going for most quality per time drysifting also loses in that category for it’s time intensive cleaning process of the material to get to 90% purity. Don’t get me wrong I love drysifting and such fire as this fullmelt drysift from CubanGrower x The Cuban Hash Queen (Pheno by TheVillage/Photographed by Erik Nugshots/Bred by Symbiotic-genetics)makes it worth it.

Cuban Grower Drysift 99% Cleanliness

But to be profitable with that kind of premium product is really difficult and the market is not that big. So in order to sell at a lower price, but still nearly the same high quality as with drysift only ice-water-hash remains an option. “Why not just blast it all”?

Good question, and yes you could do that, but the price for bho currently is not as high as decent hash rosin. Additionally the startingcost is really high if you want to do it right. If you need deeper info on hydrocarbonextraction and it’s specifics, visit Murphy Murris Instagram account

And for home users I wouldn’t recommend it either if you don’t have a proper, safe setup and are quite experienced with hydrocarbon handling. Hash on the other hand doesn’t need a C1D1 room or other security measurements than a rubber mat on the slippery floor.

So if you want to make fullmelt the fastest way possible use ice-water-hash to separate your resin like the italien hashmaker slite23 from Barcelona with this beautiful Sundae Driver 149/90u Fullmelt (Pheno by Alorganics). Now we will look a bit further into the mechanics behind hash-making in order to build a good knowledge base, that will let you achieve resin like this with a bit of practice.

Fullmelt Hash by Slite23

The principles of Hash-making


In the first part of this chapter we will look at some basic terminology that we need to describe the process precisely

  • Micron: This term refers to the opening space in the bubble bags. It tells you how many micrometers the wholes in the screen are wide. These mostly get abbreviated as “u” or “μ“. To put that into perspective, a human hair is 75 micrometers thick and our eyes can only see down to 40 microns. Thats why it’s important to buy a scope and look at the holes in the screen to see if they are all open and not clogged with nylon or bad stitching. Always wash your bag properly before using them. For washing the first time after buying new bags, I would recommend to make a 10% alcohol/water solution and rinse the heavily. But be careful not to rip the seams.
  • Terpenes: These pure hydrocarbons are a part of the famous entourage-effect firstly mentioned by Dr. Ethan Russo in his paper “Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects” (see source 1) They induce a synergistic effect in combination with Cannabinoids in your brain, basically pushing the high in a certain direction. Like Limonene for example, that on its own already causes a sort of high if you breath it in at a certain concentration. Similar to that strains with high linalool make you relaxed and the same for other strains with a lot of terpenes. There are also other components like thiols and alcohol esters in Skunk e.g but they aren’t as well researched as terpenes At last there are also terpinoids, which are similar to terpenes in effect and structure, but the have additional chemical groups. But because of their similarities we mostly count them to the terpene content.
Different Terpenes Cannabis
(Source 12)
  • Fullmelt: We already used this term in this article and some of you probably wondered what that means. It stands for the quality of the hash in regards of melt % tage. Hash that melts like water in your banger and nearly leaves no residue is the best of the best in hash. At room temperature it sometimes already melts into a oil like mass of trichomes. More info on what differentiates the melt further and how you classify it will be discussed in the chapter Rating-Systems
  • Contaminants: All particles that aren’t trichome heads be it hairs, skin, dust or plant particles are considered contaminants. More on how to prevent them and proper hygiene in the coldroom in the designated chapter
  • Cultivars: Every plant that is derived from sexual reproduction is, like humans, different even from his siblings. This term refers to one unique genotype with a specific phenotype that gets expressed. So for example just because some Cake clones yield not all of them will and even if you have a selected cut it might not dump a lot of weight if grown under completely different conditions like those that it was selected in. That’s why it’s good to ask the clone seller how it was selected or select your own cultivars
  • Flowrate: Like in coffee brewing you can control some parameters like speed of water drainage and with that force that pushes through the screens. Using that you can safe time by not having to spray and rinse that much. But that needs the perfect speed and that takes practice as you have to be careful not to blast the water through as that could drag contaminants through the higher micron screen and also degrade your trichomes by removing more terpenes than necessary. But not enough pressure prevents the contaminants from getting flushed through
  • RO-Water: Growers already know the term, but for everyone else: it refers to water filtered through a reverse osmosis filter. This device pulls out all the minerals and other compounds that could affect the taste. For optimal results you should make your own RO-Ice cubes (Protip: Insulate your washing vessel to save ice and prep time)
Reverse Osmosis vs Osmosis Principle
Reverse Osmosis vs Osmosis Principle (Source 11)

The Separation Process

How exactly can you isolate the trichomes without plucking them off one by one? For that to work we need Physics. Trichomes are secretion-organs with bulbous, oleo-resin filled heads on them. The oleo-resin is trapped by a layer of lipids that releases terpenes and other compounds slowly over the day on the plant to fight of pest. It also shields the flower from UV-Damage so to increase your trichome-coverage you should incorporate UV in your lighting mixture.

As we know from chemistry class, fatty substances don’t mix well with water as they’re non polar. This phenomenon is the reason why trichomes stay intact while beeing washed most of the time. If your strain as a to thin lipidlayer the trichomes smear in the bag and you won’t catch most of them

Thevillage Trichome Close-up Shot
Trichome Close-up shot by theVillage

That’s why some cultivars won’t produce hash yield numbers that justify washing the material. Even if it has a lot of good trichomes you have to separate them completely in order to catch all. Therefore they have to be evenly brittle, but not brittle.

Thats where water comes into play. This natural “solvent” stays, even with ice, at 0-5°C for the whole washing-process to insure maximum Quality and efficiency. Now that we have the Trichomes ready for action we will start the stirring process. If you’re hand-washing try to get a small water vortex as the current of the water strips the flower from the Trichome heads.

If you picked a good cultivar the water should turn slightly golden/purple (depends on the strain) and you should start to see the heads drop to the bottom of the wash container. If you think you got most of them, you can stop agitating and let the trichomes settle down. After that you skim the water on top that doesn’t contain resin and either filter it or throw it away. Let about 1-2/3s in the wash vessel and strain them through the Bubblebags.

How to collect the Resin from Water

But in which order do I have to put the bags in? We go from big to small openings but how many bags you have depends on your bag-set. Different companies also use different mesh sizes but most of them are in the same region so we want to give you a small List of bags that there are.

  • 220μ = Filter-/Workbag: most of what’s catched here is dust and plant material. This is to clean up most of the contaminants before catching anything. If you buy one that is big enough to fit into your washing vessel, you can wash in it and pull out most of the plant material even before emptying into the filter vessel.
  • 180μ = Second Filter: Most bag-sets don’t have them but they’re a good option if you want to add another filtration process to your regimen. Most of the heads catched here also don’t have a lot of value
  • 160μ = Rosin-/Foodgrade: This bag collection is worth it, especially when you grow strains with really large trichomes like a GMO. You can even find some partial melt in here, but I would recommend to turn this into rosin or edibles/RSO as most of the time it is still a bit dirty.
  • 120μ = great Quality Resin: This is where the real fun begins. In this range you start to see real fullmelt or at least 4 Star quality, that is either worth keeping as hash or if it’s doesn’t melt fully to press it and sell it for premium prices
  • 90μ = exceptional Melt: The melt coming out of this bag is the true Creme de la Creme and goes over the counter for astronomical prices up to 130$/g. The fullmelt nearly leaves no residue on the banger and the taste is amazing. As said before, all non melt result should be processed to rosin or oldschool hash (Frenchy Cannoli-style)
  • 70μ = is used more like a substitute for the 90μ bag. To test which one you like better, you should test wash and compare how the cultivar performs with the different bags. Most intact, ripe Trichomes are not smaller than 70μ so this will be the last bag with exceptional results.
  • 45μ– 25μ = Foodgrade: This bag catches some debris, but mostly unripe or already dried up trichomes so it can be used similar to the 160μ
  • “Full-Spectrum”: This term is a tricky one, because a real full-spectrum Oil refers to it containing the whole range of cannabinoids and terpenes. But most Water-Hash fullspec is a 45μ through a 160μ or similar micron sizes. This leaves out a lot of other compounds so technically it’s not a fullspectrum oil in my opinion. But as with everything I teach, I would be really happy to discuss these topics in the comments. Real fullspec is only achievable with solvent-extraction as it can extract everything contained in the flowers.


BubbleBags by Mila Jansen
BubbleBags by Mila Jansen
High-End Bags from Iceextract
High-End Bags from Iceextract

What do I do with the wet Hash now?

Now that you catched all your trichomes, you want to make them smokable by drying them really thoroughly to prevent it from molding. This can happen in the dry stage aswell so be fast with the process. There are two main options for drying Ice-water-hash. The first and cheapest option is air drying it by freezing it immediately after collection and spreading it out really really fine after that. How to do this and the exact steps will be mentioned in the drying chapter.

The most used method today is the use of a lyophilisation ofen also called freeze dryer. This neat piece of equipment uses certain physical phenomenons to quickly remove the moisture from the trichomemass. It also is the most terpene and colour preserving technic for drying. For commercial ops this device is essential for production speed and success as a failed air drying attempt could cost you a lot of money.

How to prepare yourself before setting up a hash lab

Now most of you probably would want to immediately wash their whole crop, but before doing that, we need to set up a proper lab and everything that goes with it. For starter we need the most essential item to be of the highest quality possible. Of course I’m talking about the starting-material as it is our base for good hash. That’s why the mantra for most hash makers is: “Fire in, Fire out” To give you an idea of what I mean with that, we will look at our material in depth and disect what makes good Hash starting-material

The different aspects of good startingmaterial

Live vs cured Flower

The first choice with have to make after harvest is whether we want to make “live” or “cured” hash . These terms refer to the drying process of our material. Live Hash is taking the fresh flowers and directly freeze them for washing. That way, you can conserve the most terpenes especially those that flair of easily like monoterpenes. This brings more sharp, intense flavor that many people nowadays really enjoy. also the colour gets “better” more easily with this method as nearly no degradation happened. What we mean with better and which role colour plays in hash, can be looked up in the designated chapter With this method it’s vital to have an extremely clean freeze, if possible you should have a separate one only for fresh frozen flower. But if you only wash once every 2-3 Months this isn’t really worth it, so you can use tupperware to protect your buds from the other freezer content.

Cured Hash Rosin
Cured rosin by Mammoth Melts from Rhode Island (Source 8)

Often the whole plant gets frozen for this purpose so you will sometimes see the term WPFF on your bought hash. This stands for “Whole plant, fresh frozen”

Live Rosin High-End Example
Sour Diesel Live Rosin

Cured Resin on the other hand has a more “rounded” flavor as the highly volatile Monoterpenes have flaired of or turned into another terpene profile. Most of this is still in research, but you definitely taste a difference. This rosin is bit harder to get as light in colour as the live version, because the dry time has to be perfect. But as we will see in the further chapters, colour doesn’t always say much about quality.

How to visually rate Material

Now that you picked your methode of choice, we can start to analyse if our product will be cut out for making hash. As mentioned before the trichomeheads and their size play a mayor role in it.

Trichome detailed description
Trichomaufbau Schema Quelle: Hightimes

First of all lets look at this depiction of a trichome. This shape is what you’re looking for in the perfect trichome category. It has a large bulbous head with a really thin “neck”. This is what we want as it will make it easier for us to break them off and separate from the plant material. What we don’t want are secretory glands without heads, their “hairs” may look frosty af on a plant, but if you wash them, you will be really disappointed. A typical strain with these attribute is purple punch. It looks fantastic but washes really bad most of the time. Another unfavourable trait for hash making are varieties with really long trichome stalks, small heads and a thick waxy cuticle as they won’t contain a lot of active compounds. These strains are also valuable, but just not for water hash.

Don’t get me wrong, if you select a fire cut, it can dump, but you would have to go through a lot of cultivars to find one. I recommend 20-50 regular seeds depending on the breeder. You can do smaller hunts, but the probability of finding a keeper cultivar that satisfies both quality and quantity aspects will be quite low. 









The importance of hash specific breeders

This is where the breeders come in. If you want to select a hash-cut but don’t have the time to sift through hundrets of plants, you should pick a breeder that selects for hash. That will give you a lot higher starting chance of finding a good specimen as the breeder has already pre selected the genetic material. There are lot of different great breeders and most probably I will forget to name some and I’m sorry if I left someone out. But to give you a direction, here are some breeder recommendation from my side: Karma genetics, Oni seedco, Bloomseed co, Dying breed seeds, Archive Genetics, Truecannabliss and Cannarado to name just a few.

Some strains especially are good for hash-making as they have a high rate of successful cultivars. Names like GMO, Sour diesel crosses or the famous Gorilla glue are well known for their ability to dump wpff yields upwards of 5%. Even most crosses with there lineages will give you your desired results so they’re a good starting point for your hash-journey. For companies I would also recommend to implement a really heavy yielding strain at all times in their rotation as a safety net, if some new selections perform worse than expected.

Now that we have picked a good strain, we can start growing and watching it. When the heads are nearly finished you can scope it with a jewelers lupe or a electronic microscope. This should be done extremely thoroughly because if you don’t do it and do a test wash, you potentially waste money and thats not good when you’re starting a company. To give you a comparison chart we depicted one picture from a study by Dr. Potter

Trichome Types in Cannabis

Figure D depicts the best usable trichomes as we don’t need excessive force for separating these from the stalk. Trichomes like in figure C aren’t the optimal, sure they have a large head and contain more oleo-resin than the ones in figure B, but they require so much force to get separated that there also is a lot of potential for contaminants to get into the product. All these criteria are only the beginning of a long r&d (research and development) journey that should look at terpene-make-up, terpene Content, rosin yield, stability, colour etc

The distribution of Trichome size

Another important performance indicator is how much a strain dumps in each quality area. A cultivar that puts nearly all its resin out as fullmelt is much more valuable than one that produces 70% edible grade hash. As with every property of hash that we look at, we need to do our tests here as well.

For this purpose you should use a register/excel sheet to get an overview of your data. This data is a treasure chest of usefull information about your process, that can give you the opportunity to optimize every little detail. This would be a example of how to analyse a strain:

  • Terpene make up
  • Terpene content
  • Yield WPFF vs Cured
  • Market value
  • How long is the overturn time (harvest-harvest cycle)
  • Trichome Size
Trichomesize distribution Alchimia
Trichome Size Distribution Visualised by Alchimia

How to test your cultivar for yield beforehand

To test and find the perfect cultivar is quite a challenge so I highly recommend keeping a cut from said plant. Not only for hash making, but for sharing /selling the clone. The high end concentrate marktet is really hot right now and new, good clones go for a lot of money. So this would be the perfect example for horizontal expansion of your production line.

But to get such a cut, we have to select and before selecting we should do some tests. The first is a cannabinoid and terpene test which you need regardless as a commercial cultivator. If you buy flowers you should ask for their Coa so that you can compare your yield to the given data and check if you catched all the trichomes. This is also a great opportunity to fine tune your normal washing processes. So if you don’t get the same % in yield that is given in the testresults you should go through your process step-by-step in order to find the mistake. If you don’t find anything, it could be the strain. Look at how the resin handles the water and if it smears the bags. Most times this is a large opportunity for product loss.

If thats not the problem, try using the leftover material for edibles/rso, that way you can use every little bit of the material and minimize loses.

COA Hash Rosin Cannabis

Another test is the mason jar shake. This simple method has a bit more to do with experience, but is also usable for beginners. You simply take 10-15 grams of your desired flower, put it in a mason jar together with Ice and water. After letting it sit for 2-3minutes you can swirl it around a bit and then you should see golden trichomes dyeing the water golden. Let it sit for another 2 minutes without stirring and look at the bottom of the jar. There should be a small layer of trichomes if you have a fitting cultivar.

Cultivation Techniques for better Hash

Swabianextracts King Sherb Cannabis Flower
King Sherb ( OGKB V.2.1 x Blue Sherbert ) grown by SwabianExtracts

The best way to get great hash yielding flowers is to grow them yourself, so that you can learn the subtleties that go into growing the best hash flowers. One sure way to increase resin content is adding UV-lighting to your grow as we mentioned before. This lets the flower build up its defences against this high energy radiation. Not directly for resin content but for terps, most hash cultivators use organic living soil system to grow as this lets the plant fully express its genetic potential. This debate is highly discussed in the hash community so I don’t want to get too deep into it. But it has to be said, that salt based fertilizer can also achieve great hash if they’re perfectly tuned in for the cultivar. A general booster for terps and secondary metabolites is a healthy amount of sulfur in our regimen. Organic growers can use gypsum or epsom salt for this purpose

The necessary Equipment for Washing

Now that we know our basics and how to choose material, we need to look at our setup. To configurate it the best way possible we need to choose between the two kinds of washing. A pros and cons list should be sufficient to give you an idea of what you want to choose

Hand vs Machine Washing

Pros washingmaschine

  • Multiple maschines can be operated by one employe
  • Less manual labour
  • simple SOPs can be made for unexperienced operators
  • “easy” for beginners

Cons washingmaschine

  • Lots of work to keep perfectly clean
  • High initial investment cost
  • cheap maschines need a draintube change in the beginning
  • often not very customizable

Pros Handwash

  • Easy to clean vessels
  • Fully customizable washing program
  • Really gentle on the material
  • Smaller initial investment
  • Large batches of 10-15k grams possible

Cons Handwash

  • hard physical work
  • Not automated
  • Experience is needed to get perfect results

The next big decision is whether to air dry or freeze dry. But it would blow up this chapter so we will look at this in the specific chapter.

A short Equipmentlist

Now for a better overview we collected a list of small and big items every wash room needs in order to function properly.

  • Bubblebag-Set (+ Workbag)
  • RO-Water
  • Ice-cubes (Ro-cubes if possible)
  • Washing Device (Maschine vs Vessel)
  • Stiring device for handwash (stainless steel paddle)
  • Drainvessel for filtering the hashwater (should be big enough to mount the bags in it)
  • Thermometer for water temps
  • Extremly clean work enviroment
  • AC for cooling the room
  • Cleaningagent (isopropanol 70% works best)
  • Waterhose with RO-water to spray down the bags
  • Cold Spoon for collection
  • Dryingdevice (Freeze Dryer or Microplane/Sifter)

How do I prepare my tools?

The most important factor is cleanliness, I know I sound like a broken record, but as everything gets concentrated with hash making, the dirt also gets concentrated. Thats why the phrase: “cleanliness is next to godliness” fits perfectly for hash making. You should start with your wash room and wipe everything down with a 50/50 alcohol/water mix. Because if you only clean your tools and put them back into the room, they get contaminated aswell. Even the ceiling and the walls should be cleaned as dust can settle there.

Next we need to take a look at our tools. They also should get wiped down and put in a cold place as the resin won’t stick as much then. Your Bags should also get washed with a very mild alcohol/water mix and then rinsed with RO-water. After that you can put them in the drainvessel over night in order to dry them.

Bubblebag Sizes from 45 Micron to 220micron

If you make your own ice you can make it the night before with RO. The best shape in my opinion is half round about the size of your thumb. This minimizes the surface and thus lets your ice stay longer like this.

How to keep proper hygiene in the coldroom

We explained how to clean your room + tools, now we go to the steps you can take yourself. The biggest vector of contamination is the human, so in order to mitigate this risk we wear the corresponding PPE (personal protection equipment) Lab coats are a standard in most hashlabs but a full-body tyvec-suit would be more appropriate for this usage as it contains the dirt on your trousers as well.

Tyvek Suit for clean Hash Production

As you can see in the picture a mask and glasses are also a good thing to contain bacteria in your breath and skin pieces. But thats more important if you’re in the medical sector. For home use you can get away with a suit, a hairnet and proper nitril gloves. These are really practical as your hands would get sticky really really quick without them

Nitrilgloves for clean Hash Production

A coldroom buildout

Now that we protected ourself and the hash from contaminants we need to build a coldroom that makes our job as glorified janitors easier.

The best working surfaces

The first thing we should direct our attention to are the surfaces. Every desk, floor and wall should be wipeable as they collect dust. The best option would be to use stainless steel everywhere because it can be safely sterilized heavily without showing any degradation. Another reason is the faster cooling off the room because of it being metal. But such coldrooms are really expensive and only for professional operators For the homeuser, I would advice to lay out paintersfoil on the floor and walls. Looks like out of the movie american psycho, but trust me it is worth it. Also it is quickly removed if some uninvited guests want to look into your flat

Painters Foil for Contaminationprevention
Painters Foil

I would also clean the ceiling with a broom or a mob and some water if possible before washing. If you want to be really thorough, you could put in an air filter. You can use a normal carbonfilter similar to the ones in growtents.

How a professionally built shell for your coldroom

Optimal climate control

For washing and separating we need constant temperatures around 0-10°C to get the best results. Otherwise the hash will get greasy and really bad to collect. This is quite difficult if you don’t have well insulated place to wash. That’s why we recommend using cellars or insulated sheds for home users. If your growroom is clean and sufficient you can use it as well, but every room needs a strong AC to wash in the summer months. But how do we know which one to buy? This depends on your budget and coldroom-size. Most Acs are measured in BTU/H or Watt/H which can bei converted into each other. 1000BTU/H are equivalent to about 300 watts/h and how many of those you need can be looked up in the chart we made

Space Watts
Up to 30m2 2350
30-37,5m2 2500
37,5-42,5m2 3000
42,5-50m2 3500
50-60m2 4000

But not everyone can afford the best Ac so we’re going to look at some models for each price class

Small to medium budget

In this category we have the well known mini splits, which most of you will have in their grow room. This modell is really efficient and in my opinion the best choice for small to mid sized ops as you can get down to freezing temperatures in a medium insulated place because it doesn’t use air, but a refrigerant. They’re powerefficient and don’t take up to much space, but it needs a second device on the outside of your building which has to be connected via copper wiring. That and the cleaningafford are the only negativ points about this system. You can get them as cheap as 800$, but you have to count in the installationcost if you’re not doing it yourself. But DIY is only recommend if you’re a professional or have done it before as improper installation could be a fire hazard. 

Central AC Units
Central Large-Scale AC-Unit

These ACs are really powerful and normally used to cool entire houses. Thats why they can be quite expensive and use lots of power. If you buy one of these and use them all the time, you should think about buying a solar panel as this would pay for itself pretty quickly. This model is mostly used when already preinstalled in a large grow or a housingcomplex You will need a licensed electrician for this installation as this is really complicated and easily done wrong, which again poses a fire risk

How to setup a coldroom for good workflow

Now that we set up our basic shell for the coldroom we need to bring in our equipment. If we want proper workflow for e.g. commercial use (most hash/time) we have to think strategically on how to setup everything in an order where you don’t block others from doing their part. So in order to give you an idea what one could look like, we depicted a example in here

If you don’t understand all the terms, no problem, we will now take a look at the step by step tutorial. This should clear up most of the confusion

A step-by-step approach to washing Ice-water-Hash

So we have our room prepared, material sourced and ourselves clothed accordingly. Let’s beginn the best part, the wash It’s advisable to really check if you have everything you need in the room as opening it again could introduce more contaminants in your room Have the icecubes stored in the freezer aswell so that you can directly take more if you need it

Our material should either be frozen or dried and ready. First we prepare the material by breaking down larger nugs in thumb sized pieces in order to get the optimal surface area while not making them so small that they get grinded up between the ice. Be really gentle with the buds as every handling “destroys” trichomes and with that, reduces your yield.

Gastown Cannabis Flowers Mimosa
Mimosa Bred by SymbioticGenetics Grown by Gastown-Collective

When this step is finished, we continue to loading up the wash vessel. First put in the workbag, then a thick layer of ice to cool right off and keep the material from being scrubbed against the bottom of the vessel as we’re trying to not damage the buds too much. Now put in a layer of material in (a bit thinner) and then a thin layer of ice again. Repeat this till all your material is in

After this, it’s time to get it soaked. Use a gentle setting on your water hose and distribute it evenly over the mix until everything is floating. You want the right ratio of ice/water in order to keep the mix cold but not grind the material between ice cubes. Again, the water vortex is whats separating the trichomes from the flower. The best indicator is listening when you stir it up. Maybe do a testrun beforehand without material to get the mix right. There shouldn’t be any crushing noises instead only a light collision sound of single ice cubes hitting the side of your vessel. For a example of this sound and maybe one of the greatest videotutorials out there visit Frenchy Cannolis Youtube channel for his course on hash

Prewash Bucket with Cannabis&Ice
Pre-wash soaking material by KENNWALL

Let the material sit for 5-7min for WPFF and 10-12min for dried flower in the water to resoak. We do this to let the flower get more flexible so that it doesn’t release to many contaminants when agitated.

Then we beginn with the stirring process. Remember to be gentle to the material, but stirr it thoroughly to get everything nicely mixed. You can start with clockwise stirring or a canoeing like move. Continue this for 5-10minutes depending on how golden the water is and how many washes you want to do. If you want to get everything out in one wash and don’t care too much about getting the cleanest of the clean fullmelt you can go long 10-15min. This method is quite time saving if you only go for rosin. If you want to separate every grade of hash you go for 5-10min depending on the strain/stiring strength.

We stop stirring and let the trichomes settle for 2-3 min again so that we can skim of water from the top. We do this as it would be really heavy to empty out the vessel in the drainvessel if it’s completely filled. If you’re running a maschine you only set the timer and come back to open the drainvalve on the bottom to release the water into the drainvessel. I would advise you to take your sprayer/hose and spray down the drained leftovers again as a lot of hash gets stuck between cubes/material if you only drain it from the bottom. Now that we have our bags “filled” we spray down every bag down like this to get contaminants and contaminants pushed through. We continue this with every bags because trichomes that are the right size don’t fall through if they’re in the right bag (micron = trichome-diameter) and the contaminants fall through to the last bags if you did it right. How to that properly we will watch a video of eldaggy of him spraying down his hash

Afterwards we can scoop the hash from the bags with our spoon that we put in the freezer earlier. It’s advisable to cool 4-5 spoons as they warm up pretty quick again. Now depending on our dry method we put the hash on our trays and spread it evenly to not get any water pockets. If we freeze dry we can put it aside/directly in the dryer. If we air dry we need to squeeze out most of the liquid with a 25micron screen, cover the hash and put it in the freezer in order to microplane/sieve it later on. We can repeat these steps until no more hash comes out or we don’t like the work/quality ratio anymore and use the rest for blasting/alc extraktion

How to dry wet Hash

As we can’t smoke wet hash we have to dry it now. And as said before we need to decide between air/freeze dry as a home hash maker. For commercial washing you can’t use airdry as the risk of productloss and the dry time will make it unprofitable. I mean you can do it, but in order to make enough money of that you need brandawarenes.

Whats a Freeze Dryer

This lovely device is also called a lyophilization ofen and dries your hash in a short time. It does this by freezing it down to about -40°C and then slightly heating the trays with the hash, causing the remaining moisture to directly sublimate into a gas. This effect is encouraged by a vacuum that you pull on the drying chamber. This leaves the highest possible content of terpenes in your hash and prevents it from oxidizing which would darken your hash aswell. For info on how exactly this works and how a freeze dryer looks like we will watch a short video from a big drying manufacturer

For the tech heads under you, we have a second option to buying a prebuilt unit. There is the possibility of building your own freeze dryer. This will safe you a lot of money, but beware, it won’t give you the same results that a commercial, specialized unit will give you. Here’s a short video tutorial

How do I choose and use a Freeze Dryer

Let’s assume you want to buy one of these babies but don’t know where to look. We would recommend different models depending on your capacity needs and budget. First we have the harvest right models, these are what most people use in the industry as they beginn at 2500€ and a capacity of 800gs of Hash each day of usage. The only problem is the customer service and life time of these maschine as they require intensive care especially with an Oil pump. The second brand are labconco dryers. They get used in the pharma space and are the Ferrari under freeze dryers. These units are built for a lifetime, but also really expensive as they begin at around 15000€. We would recommend them only for commercial users as they won’t make sense for the home user.

But then there is another decision to make. Do I go for the cheaper oil vacuum pump or do I invest in an oilless version

This mostly depends on your budget as I would advise you to always go with the oilless version as this is way less work. You would have to regularly check and change your oil and if it malfunctions you get oil all over your hash. But the oilless version also costs an extra 2000-3000€ depending on the manufacturer.


This brings us to our next point: how do I use my freeze dryer? We already told you about the pump maintenance, but this is not the only thing you have to check before using your dryer. Before each cycle you should check the drain valves. Let out all the drainwater and the close it again tightly, because if you forget that you won’t be able to produce a full vacuum. Now we clean the inside of the dryer and remove any leftover ice (if you haven’t defrosted). We connect the pump to the dryer and inspect the doors if they fit snuggly on the sealing part that guarantees the ability to pull a vacuum. If we prepared our trays right and they look like this we can load them into our FD and start the process. This will take about 24-36h depending on how thick your hash layer is

Full Water-Hash Tray for the Freeze Dryer
Full tray of wet hash by Kennnwall

To check if it’s dry, take a card and move the hash around a bit. If it behaves like sand and has no clumps left it is dry and ready for smoking or further processing

Drying Hash without a freeze dryer

This method is mostly used for home made hash for it’s cheaper tools. As said in the washing guide you should immediately freeze your hash after collecting until it’s a hard brick. This gives you the opportunity to separate the individual trichomes better in order to get more surface area for water to evaporate. You need a temperature controlled room with about 30-40% humidity at all times! The room should also be clean to insure no mold spores get into your hash and multiply.

Traditional Hash Air Drying Racks
Drying Room from Aqua Tech Labs

Now you take baking paper sheets and lay out your drying area. You can use baking trays in an open room setup or put it in a clean (!) pizza Box as the cardboard will pull out even more moisture. Then take your frozen hash bricks and grate them either with a microplane or a siever finely over the paper. Be careful to really spread it out good as clumps may lead to inconsistent drying. Wait approximately 1-2 weeks and check regularly for dryness.

How do I calculate my yield from flower to Hash

Now that we weighted out dry hash and have a g number we can simply take the % Value e.g. 5g Hash out of 100gs Flower would equal a yield of 5% These values differ greatly between WPFF and cured Hash as you have to subtract the water weight from the fresh frozen flower. The fresh flowers are about 75-80% water so 5% is a high yield compared to cured hash yield where 20-25% would be a good yield. Good fresh frozen yields are between 3-8% depending on the strain, 8% being the top of the top. Most times these numbers are only achieved with selected cuts asa lot of strains yield <1% For cured Hash a good range is between 15-30% return, but this also requieres a hash specific cut

More Hash-Education

If you want to learn more about Hashtech and Hash culture visit my buddy over at TheHashishInn and listen to his Podcast

What does colour say about my Water-Hash

This is a very controversial discussion in the water-hash space and I hope to not step on anyones to toes, but this needs to be said. Colour doesn’t affect the quality of Hash! Most use this phrase but forget to say that, while this is true, there can be bad dark hash. Sometimes it’s not a sun ripened or cured resin, but just contaminants. This is a important factor to consider when buying Hash. You have to look really close and do the ultimate test: how does it smoke! No real hash connoisseur cares about the colour when the flavor, smoothness and high is right and so should you. Some people go as far as harvesting way to early in order to get the whitest hash, while it only leads to a speedy, weak high and nearly no flavor

“Dark” or better said amber hash can come from strong UV-Radiation, CBN-Content or long air exposure which oxidizes the compounds in hash

How is Hash rated?

Most of you will have heard about 6 star hash or lower quality, but exactly is that measured? Tbh the star-rating system is used quite liberally so a lot of “six-star” hash is worse or not even close to being fullmelt. To give you a quick overview of how it should be used and a measurable alternative shall be given here

The star rating system

1-2 Star

This grade is mostly used for edibles/RSO or further cleaning processes as it’s from low quality. You can identify it by it’s green/dark colour that stems from the high content of contaminants. You will typically find this in the 180u or 25u bags

3-4 Star

We use this grade of water-hash for edibles on the worse end and on the better end of the quality spectrum we press it to rosin as this will still yield a proper, terpy oleo-resin. Typically found in the 150u Bags and characterized by it’s light colour but missing meltyness

5-6 Star

This premium product will be processed to high-end-rosin on the lower quality spectrum and the best of the best will be left as it is if you have a market for melt. If not, you can also press it and sell it for the maximum rosin price, but beware I will call it a sacrilege to press such high quality melt haha True fullmelt shouldn’t leave residue in your banger. A tiny bit is normal as the trichome heads still have their waxy cuticle and this “burns”

The gravimetric measurement, a good alternativ?

As you might have noticed the star-rating leaves a lot of room for interpretation and therefore is unprecise. Fletcher from Archive Genetics wanted to adress this issue and bring in a measurable test. As he was the one to bring freeze dryers into the hash industry, he has a lot of credibility in this regard.

His method is to use an enail, take a 15micron metal screen and weight it before. Now you put exactly 0,1g of your Hash on the screen and put all that on the enail until no oil is left. Then take the screen and weigh it again. Now subtract the previously taken screen weight and there you have your residueweight. This also can be converted into a %melt value which should be used to categorize the Hash Visit his Instagram for fire flower and melts

Sieh dir diesen Beitrag auf Instagram an

Let’s end the star system for water hash, solvent less, ice wax, and move onto a system that accurately grades how “MELTY” your hash really is. just simple gravimetric analysis and it’s relatively accurate for the end consumer’s needs. Tag your favorite hash maker in this post! @trichomeheavyextracts1 @k3nnnwall @cannabisreverend @kush4breakfast @710labs @3rd_gen_familyfarm @resin_ranchers.pdx @hashcamp @icedoutextracts @beezlegardens @theccc420 @dannyflavors @shane_omac831 @pureoptions @jungleboys @jungleboysfullmelts @humboldtorganiccollective @michigan_made_melts @icextract_equipment2.0 @cubangrower @tharealogkushman @eldaggy @turtle_trees @megaraw_melts @voodoomelts @solventlessismore @puaextractions @fullflavaextracts @golden_trichome_extracts @dankczar_icewax @connected.california @alienlabs @returnofthealien @ogkushbreath @therealogkushstory

Ein Beitrag geteilt von Archive Seed Bank (@archiveseedbank) am Apr 19, 2020 um 6:09 PDT

What can I do with my finished product?

This depends on your needs, but most people dab/press it or use it for high end edibles. If you process it to rosin you can also make carts with it or fill preroll “donuts” with it as this is quite popular right now The leftover washed flower can be freeze dried and be blasted/alc washed to get every cent out of it. If you already separated all trichs you can use it as mulch for your garden aswell. I hope you learned something new and had fun doing it. If you have any tips/tricks or corrections you want to be included, feel free to leave a comment or shoot me an email as I want to improve the quality of my hash making aswell and you never stop learning Happy dabbing everyone PS: Sorry for my english, I’m not a native speaker 😀

Disclaimer: This tutorial is intended for legal use in legal states only. We do not condone any illegal activity


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