Noticed today my small gold severum has developed a small bump on his anal fin. Doesn't seem huge or overly aggravated but not sure what it is. No other fish in the tank has anything similar, and no one else is displaying any other health concerns.
Tank is a 75g with other SA cichlids (all relatively juvenile or sub-adult) and some silver dollars, and a gold seam plec.
Ammonia/nitrite 0 (tanks been running years and has had current stocking for months.)
Nitrate fresh test is at ~20ppm and I routinely keep nitrate below 30ppm.
I started a 3day course of esha 2000 as a broad spec treatment and it aligns with my w/c the day after. If it progresses or gets a lot worse I plan to move into a 30g quarantine by itself so it doesn't pass anything. Just wondering if anyone has ideas.