Swim did 4 mini-extractions (~20 g each) and got alsmost no spice. In all these extractions mhrb has been mixed with DE to prevent clogging. 3 extractions were typical A/B that used to yield more than 1.3% of spice. The 4th one was IPA extraction in an extractor followed by an A/B. It used to produce ~1% of spice in the past. Powdered mhrb is from the same batch that is being kept in a freezer.

Swim used Becogur 3500 that supporting literature describes as coarse. It is used for clarifying of liquids with a lot of turbidities, although it looks like pretty thin white powder. This is swim's first experience with DE, so she doesn't know if it is normal. It has been bought in the original packing, so there is no reason to believe it is something else.

Did anybody experienced similar problem?

...bump...

I haven't tried this yet, but I am wondering about the same thing, as I've learned that diatomaceous earth is sometimes put on top of activated carbon in a filtration process and I am not very keen on having my alks trapped in either DE or AC...