Bubble Hash

What is bubble hash?

Bubble hash is hashish obtained from the cannabis plant using ice water and fine filter bags. The cold makes the resin glands of the plant (trichomes) brittle, they come loose when stirred and are caught in bags with different mesh sizes. After drying, what remains is a grainy concentrate of trichome heads that is left loose or pressed. No solvents are used in the process.

Many names are in circulation for the same process: Ice-O-Lator hash, ice hash, ice water hash, water hash or bubble hasch. In German strain lists, it is often called Frozen Hash. The comparison further down shows what sets bubble hash apart from dry-sieved hashish such as Dry Sift.

Note: This page is a factual guide to hash types and production methods. In Germany, hashish containing THC is subject to the Konsumcannabisgesetz (KCanG, German Consumer Cannabis Act), and medical cannabis to the Medizinal-Cannabisgesetz (MedCanG, German Medical Cannabis Act). Retail sale is not permitted. The information on methods and THC content describes classic hashish from the cannabis plant, not products from our shop. We don't stock bubble hash.

Ice-O-Lator: how the ice water method works

Ice-O-Lator was originally the name of a filter bag system from the Netherlands. Today the term, also written Iceolator, mostly stands for the method itself. MacGowan and Martynenko describe it in the Journal of Cannabis Research (2025) as wet separation: flowers are mechanically agitated in ice water, the resin becomes brittle and the rest of the plant material stays flexible. Because trichomes and plant parts differ in weight, they can then be separated.

Besides manual work, there are also machines for the stirring. Online, people often talk about a bubble hash machine or washing machine. This means devices that work like a small washing machine with cold water and move the material evenly. That does not change the principle, it only saves manual work with larger quantities.

You deliberately won't find instructions for making it yourself here. In addition to the general prohibition on handling cannabis, § 2 Abs. 2 KCanG states explicitly: “The extraction of cannabinoids from the cannabis plant is prohibited.”

Bubble Bags and micron fractions

The filter bags are called Bubble Bags. In common sets, the mesh size ranges from about 220 to 25 microns. Each bag holds back its own fraction, which is collected separately. The coarsest bags mainly catch plant parts and broken stems. The middle mesh sizes are usually considered the purest fractions, because that is where most complete trichome heads get caught. Smaller fragments and dust collect in the finest bags. So if you read a micron figure in a strain list, it tells you which bag the material comes from.

Drying bubble hash

After washing, the material is wet and has to be dried. MacGowan and Martynenko call this step a drawback of the method, because it is laborious and residual moisture encourages mould. Producers dry either in the air on a fine screen or by freeze drying. Freeze drying is considered standard for the top quality grades, because it preserves consistency and aroma better. Another point from the same source: part of the volatile aroma compounds (terpenes) already passes into the water during washing.

WPFF and Fresh Frozen: the starting material

Both dried and freshly frozen plant material is used for bubble hash. WPFF stands for Whole Plant Fresh Frozen: the whole plant is frozen directly after harvest, without being dried or cut up first. The aim is to preserve as many aroma compounds as possible that would otherwise be lost during drying. WPFF hash is therefore bubble hash made from such material. The abbreviation often appears in strain lists right next to the strain name.

Fresh Frozen is the more general term. It only says that the material was freshly frozen, not whether the whole plant or only selected flowers were processed. Dried material is easier to store and process. Fresh Frozen material is also often used to make Live Rosin, i.e. rosin made from freshly frozen hash.

Quality grades: stars, Full Melt and colour

The purity of bubble hash is usually classified with a star system from 1 to 6. What is assessed is how completely the material melts when heated and how much plant residue remains.

Stars	Name	Melting behaviour	Typical further processing
5 to 6	Full Melt	Melts almost completely, hardly any residue	Stays loose or is turned into hash rosin
3 to 4	Half Melt	Melts partially, visible residue	Usually pressed into classic hash
1 to 2	Cooking Grade	Hardly melts, a lot of plant residue	Further processing into extracts

The top grades are traded as Full Melt hash. Besides melting behaviour, colour gives a first indication: light blond to golden brown suggests fresh material and little plant residue, greenish tones more chlorophyll. Bubble hash also gets darker through pressing and ageing. Under a magnifying glass, good material shows almost nothing but round trichome heads.

Bubble hash, Frozen, Static and Dry Sift compared

The four terms appear side by side in strain lists, but describe two different methods. Bubble hash and Frozen Hash are made wet in ice water. Dry Sift and Static Hash are made dry using screens.

Type	Method	Starting material	Typical form
Bubble Hash	Wet, ice water and Bubble Bags	Fresh, frozen or dried flowers	Grainy to sandy, loose or pressed
Frozen Hash	The same ice water method, the name emphasises the cold	Fresh, frozen or dried flowers	Often traded as a pressed slab
Dry Sift	Dry, screens only	Dried flowers	Fine powder with plant residue, often pressed
Static Hash	Dry Sift plus separation by static charge	Dry Sift	Very fine, light powder, loose or pressed

The most important difference between Dry Sift and bubble hash is the water. With Dry Sift, dried flowers are moved over screens, and MacGowan and Martynenko describe a setup with 250 and 74 microns. The powder in between contains trichomes, but also plant dust of a similar size. Ice water, by contrast, separates resin and plant by brittleness and weight, but costs part of the terpenes and requires the drying step. Frozen Dry Sift is an intermediate form: frozen material is sieved dry, entirely without water.

THC content and legal situation

Bubble hash has no fixed THC content. It depends on the strain, starting material, sieve fraction and star grade. A review for medical professionals (MacCallum, Lo, Pistawka and Boivin, Cannabis and Cannabinoid Research, 2023) gives 40 to 60 percent THC in general for bubble hash and ice water hash, and 50 to 80 percent for kief and Dry Sift. These are rough ranges from the specialist literature. Only the lab value of a specific batch is reliable.

Legal situation in Germany

Bubble hash containing THC is hashish within the meaning of the KCanG, which defines hashish as “the separated resin of the cannabis plant” (§ 1 Nr. 5 KCanG). Handling cannabis is generally prohibited under § 2 KCanG. Adults may possess up to 25 grams for personal use, and up to 50 grams at their place of residence (§ 3 KCanG). Exempt from the prohibition on handling under § 2 Abs. 3 KCanG are, among other things, private home cultivation and distribution within cultivation associations. Separately, the extraction ban under § 2 Abs. 2 KCanG applies. Trading remains prohibited, and medical cannabis is only available on prescription under the MedCanG. As of October 2026.

What our shop offers

We don't sell bubble hash or any other hashish containing THC. In the hash section, we stock other formats whose product pages describe strain, aroma, consistency and content. They do not mention a production method such as the ice water method. The sections above are therefore not information about these products. The page Buy hash gives an overview of all varieties. These include, among others:

• MeshFlash Frozen Hash in three varieties of 2 grams each. “Frozen Hash” is the name of the product line here.
• CBD hash in three varieties, with the CBD content of each variety on the product page.
• CBD Pollen Kief, according to the product page sieved trichome heads of the hemp flower with 14 percent CBD. Kief is sieved dry and therefore closer to Dry Sift than to bubble hash.

Sold only to persons aged 18 and over, shipping in 2 to 5 working days.

Frequently asked questions

Why is it called bubble hash?

There are two explanations for the name, and both are widespread. Stirring in ice water creates lots of air bubbles. And very pure material foams up and bubbles when heated, before it melts. This foaming is considered a sign of Full Melt quality in the scene.

What is the difference between bubble hash and kief?

Kief consists of dry-sieved trichomes that collect, for example, in the bottom compartment of a grinder or under a screen. It usually still contains plant dust. Bubble hash is obtained wet in ice water and separated into fractions using several bags. Both consist of trichomes, but method and purity differ.

How do you recognise mould in bubble hash?

Mould develops mainly when residual moisture remains in the material after washing. Signs are a white or grey fluffy coating, a musty or mouldy smell and damp, lumpy spots. Mouldy material should be disposed of.

How long does bubble hash keep and how is it stored?

Bubble hash is stored cool, dry, dark and airtight. Light, heat and oxygen make aroma and colour fade over time, loose material faster than pressed. In the fridge, the packaging should be sealed tight so that no condensation forms. There is no fixed expiry date.

Can bubble hash be pressed into rosin?

Yes. Bubble hash is often pressed between hot plates until the resin comes out as oil. The result is called hash rosin, or Live Rosin when made from Fresh Frozen material. The higher the star grade of the starting material, the less plant residue ends up in the rosin.

Is there bubble hash made from CBD hemp?

The ice water method separates trichomes regardless of which cannabinoids the plant contains. So it also works with CBD-rich strains. Whether a CBD hash on the market was made this way is stated only on the respective product page. Our CBD hash varieties do not mention a production method.