In case anyone looking for info on Azamax, I used 15ml per gallon and ran thru my NFT system for an entire day, they're all dead! SO I'm not going to call it good from there, in a week I'll do it again and run 15ml per gal for a day just to make sure. But at $60 a bottle I can only do it once more $60 a week for preventive measures is just too much..