between the Remora C and the emorer power filter, i think there's plenty of filtration going on. I'm not a marine biologist but i know my filter moves a large amout of water every hour. Onto another possibility. Parasites. Could there have been a parasite in the frozen brine shrimp i was feeding him. I doubt anyting could live after being froze but i'm just asking. (shame on me, stuipid question)
To answer the other question, I have not introduced any other specimen into the tank. He's the last fish/organisim i put into the tank myself. He's been in there probabaly a month and a half now. He's been all good up to this point.