Sore on our dojo loach, help!

[JohnPlecostamos]

Help! Our poor dojo loach has a sore on his side that’s not getting better. At first it looked like a small red spot where he scraped himself on a decoration maybe? We started Melafix on Saturday July 1st and the scrape closed, but now he has a large raised red area. It’s a lot bigger than before. He’s acting normal, doesn’t seem bothered. We have another loach and he does not have any marks on him. Not sure what to do to help him heal or if it’s more than an injury. We also did a 25% water change on Sunday the 9th.

We do currently have an issue with white mold looking stuff that we are working on getting rid of, but from what I’ve read it’s harmless to fish and eventually goes away after siphoning it out several times. I added a picture of that too. Thank you for your help!

Ammonia-0
PH-7.5
Nitrates-20
Nitrites-.5
Hardness-120
KH-80
Water Temp-76

[Colu]

Looks like a change to the tissue this could be caused by a benign growth or an infection I would start to increase water changes as you have nitrite of 0.5 add a double dose of prime prime till it constantly stays at zero I would also do a course of maracyn2 in food feeding a small amount twice a day for 7 days active ingredient minocycline is a broad spectrum antibiotic and has anti-inflammatory properties @JohnPlecostamos