While pruning back an overgrown tank I'm keeping fish in while prepping a 90g (this is a 20), I noticed a couple of otos with what I think might be Ich. Can someone confirm? Treatment for catfish? (Otos and farlowellas). Bit worried about 86F, but more so about chems.
Tank:
Ph:6.9
TDS:103
Ammonia:0
Nitrite:0
Nitrate:40 (higher than normal, doing a water change)
Tank: 75F
KH/GH: very low, always use RO water
Water changes: 5 gal (25%) per week