Sore on pleco head

[CASH2269]

So I have a 29 gal freshwater guppy tank that I’ve had going for several months now. Unfortunately, we found out my grandmother had cancer and I spent 2 months with her not able to take care of the tank. When I returned, the water tested perfectly a the API master test kit but my pleco had a whiteish tan spot on its head. I did a 50% water change and cleaned the gravel but it is getting worse. A few days ago it was showing red flesh and now it’s almost tripled in size. I’ve tried the primafix/melafix combo and followed the instructions to a T and after the entire bottles it’s only getting worse. Does anyone have a suggestion? Salt doesn’t seem to work either. Tank mates include guppies and a snail. The tank gets fed once a day and light is on for 14-16 hours a day. Also have driftwood and feed it pleco pellets

 

[TwoTankAmin]

That pic is too out of focus for me to tell exactly what that "sore" looks like. Pleecos like to hide in tight spaces. Do you have a cave for it? If not, is there a "natural hiding space it uses? Does it hide under a horizonally placed heater near the bottom of the tank?

The reason I ask is that often they have a place to hide which they outgrow. The result it they can scrape the top of their head or their sides (depending on the shape of the space) every time they go in. They will persist in squeezing into their hiding place which pretty much makes a sore that doesn't heal and which gets worse. It can get infected and/or fungus in some cases. It would help to confirm or rule this out as a cause because that will make it easy to fix.

Remove a too small cave or dismantle a narural hiding spaece. The provide something in its place. A bigger cave is ideal. Bigger would not mean huge, it means roomy.

Also, can you get a better picture and provide some info re what else is in the tank.

 

[CASH2269]

Hope this pic is better. I did have a horizontal heater he likes to stay under. As you see in the pic. So I moved it. I also had a mesh breeder basket I made for the fry to hide in that I just removed one side on so he could swim inside and hide. I recently had an issue with columaris with the guppies and lost about 25, 3-4 months ago but haven’t lost any since.