I have a 37g tank that has been setup for 7 months. I used to have 6 black skirt tetras, 6 glofish skirt tetras, 6 bloodfin tetras, 3 peppered cories. Now, slowly, I have lost a few. I am down to 6 black skirts, 3 glofish, 1 bloodfin and 3 peppered cories.
Currently I have a blackskirt with what appears to be a skin ulcer. Also, I have a glofish with some kind of mouth rot or something. Today is day 5 of me dosing with melafix. I originally started the melafix because of the skin ulcer on the black skirt. It looks like it might be getting better. After 3 days of treating with melafix, I noticed the mouth problem on the glofish. Will the melafix heal this problem? What is causing this and what can I do to keep my tank healthy? I do 50-60% water changes every 1 - 2 weeks.
Here are some pics of the black skirt and the glofish.