I have a 90g that I have a group of 12 clown loach and 5 datnoids at 6-8 inch. I'm running a penguin 350 and fx5. 1 of the datnoid only eat shrimps about 4 frozen shrimp deshell and defrost once a day everyday. My other dats are on krill diet, feeding once a day, but my ammonia shoots to 4-5ppm every 4-5 days. Is it the frozen shrimps? I thought my filtration is good enough to handle it for atleast 2 weeks. but I guess I'm wrong. These dats will be going to my establish 175 in 2 days. I have doing water about 40% every other day and treat it with prime, so the reading could be wrong on the ammonia.. I just want to know is it the defrost shrimp ? ph is at 7 so I dont think its a ph crash..