Hi all. I'm reaching out to the corycat. experts out there. I have a 75gallon that's been established for about a year and a half. I've got 7 turquoise rainbowfish 2 Bolivian Rams 11 harlequin rasbora's 2 sunset dalmation Molly's 6 trilineatus corys 6 bronze cories My water parameters are 0/0/20-40. Temp is 75.5 F. I do 30-50% pwc every one to two weeks. And, I just keep losing my trilineatus here and there. I'm wondering if they are just extra sensitive to the nitrates. Or is the temp possibly the problem?