Pleco attack markings... but no pleco in tank.. burns maybe?

[pearls-before-swine]

Has anyone seen this before? This morning I noticed one of my discus has a small spot about the size of an eraser tip on him. It looked like he had been attacked by a pleco (like the slime coat had been sucked off) but I've NEVER had plecos in the tank (only tank mates are sterbai and a pair of german blue rams). About an hour ago I started the process of cleaning out my filter when I noticed another discus had the same spots (this one has 3) on him. They almost look like burn marks from my heater... is this possible? Does anyone have a picture of discus with burn marks?

The spots are smallish, about half the size of a penny, and look very similar to pleco damage - the scales are faint in colour, but no signs of the scales falling off or sticking out or anything. Has anyone seen this before? I'll try and post a pic after I'm done cleaning my filter and have my lights back on.

[Maria Ashton]

A pic would be helpful, I dont think its likely to be burns but I am not experienced enough to say. My fish sometimes sit around the heater but have not burnt themselves - yet...

Are there any other odd signs?

[Darrell Ward]

Honestly, I've never had a fish get burned by a heater, and I've had discus lay eggs on them. The water generally takes the heat from the heater as fast as it heats, so they never really get that hot while underwater. If it didn't, the heater would quickly overheat and burst.

[nwehrman]

In my opinion - (based on my personal experience) I had the same in my Juvie tank once and it was two issues at once, water quality & fighting. Because water quality was down - (uneaten food between sponge and wall- unnoticed and missed during water changes till I did deep clean!) the aggression was up and leaving bite marks from discus to discus. Upped water changes and wiped all walls and all better there after....spots gone in 48 hrs mostly just slime layer off - I believe.

[Maria Ashton]

In my opinion - (based on my personal experience) I had the same in my Juvie tank once and it was two issues at once, water quality & fighting. Because water quality was down - (uneaten food between sponge and wall- unnoticed and missed during water changes till I did deep clean!) the aggression was up and leaving bite marks from discus to discus. Upped water changes and wiped all walls and all better there after....spots gone in 48 hrs mostly just slime layer off - I believe.

that makes a lot of sense, I have had similar experiences, I reduced feeding to try and deal with a couple of other issues and my fish became quite aggressive with each other.