I came home today to five dead Acei's. Only that breed died. But the others are seeming stressed. Not sure what flasing means but they are hanging out near currnt, darting, scatching . Can't see any signs of spotting. Did a 50% Water change and tried to raise temp. Had water tested and all levels are fine but Nitrites were a smidge high, Nitrates the same. Ammonia 0, PH 8.2., temp is around 76 which is a little low so I am trying to gradually increase. Not sure how to tell if it is a parasite or bacteria or anything for that matter. Looking for suggestions or thoughts.