I have been in the hobby for 40 years. I do weekly 75% WC on this (1 of 8) tank. I have been collecting plecos for a very long time. I have no room for QT & do buy wild-caught rarer species from the swap. That is where this disease came from. I always treat their food 1 week with metro & then another week with prazi, for IPs. Never had any other issues than that or ich.
90g, there is a very large piece of driftwood, going the length & height of the tank.
Nitrate: 5-10 (after WC)
Temp 78
pH 7.2 after WC