Rescue pleco. No experience, need help identifying aliments.

Hi there. I cross posted this to the PlecoWorld forums as well but they do not seem to be terribly active, I apologise for the multi-post. My sister and I rescued a Pleco from our friend. She wanted to re-homed him due how large he was get. We don't know anything about fish or fish keeping but are determined to do right by this little guy. We've done a bunch of research on him (enough to be relatively sure he's a common Pleco and to know how big they get ha.) and we know he'll need a larger tank but for right now we've used part of our tax returns to set him up with a 75 gallon home, it's the best we can do on short notice.

I need help identifying what's wrong with Hank. He has what I think are old injuries, ammonia burns maybe from what I'm reading? But he has a bunch of nastiness on his stomach and around his gills that I don't see on photos of healthy Pleco's. My local fish shops are all salt water based though I will make a trip out there soon to ask for advice. I picked up a few things at Petsmart while grabbing his tank and equipment. One of the employees recommended "Melafix" and "Primafix" as a general treatment. I picked those up but I'd like more opinions before I use them. As I mentioned, I've done so much research on the basics of plecos and tank start up over the last I feel like I've crammed for a exam but I don't feel comfortable trying to medicate him without experienced advice.

Thank you guys greatly for any help or informational resources you can offer. I've attached the best photos I could get of Hank's issues. You'll see what looks like skin/scale loss along his head and back, these are what I believe to be the old injuries. His stomach has something on it. From the photos I've seen I think you should be able to see his markings clearly but they appear to have a film over them. I can't tell if it's fuzzy or not. He also has a large white dot under his gill and near his tail. The spots on his lower fins are actually on the tank itself, sorry about that.

I've also included one of his old home the day we picked him up. The poor guy apparently lived in there for 10 years! This little guy is tough that's for sure. I want to be sure he gets healthy given the awful life he's had so far.

 

Is that a real tree trunk or plastic decor in the tank? They can scratch themselves on plastic, better to use driftwood

 

The piece he's attached to in the second photo is plastic yes. He has a real piece, it's leaning against the plastic trunk in the same photo. Good to know! I'll replace the plastic one.

 

Before starting with medication, I would get his new home through the nitrogen cycle, provide him with good food and fresh water, some real driftwood, and see how he develops. Clean water and a good environment is a big step forward.
Tossing medication at him he may not need may stress him out.
Ten years is young for a Pleco, how big is he? Gorgeous guy, I applaud you for taking him on.

 

Will do and thank you. He's about 9 and a half inches long. He's eating like crazy, He was getting algae wafers at his old home but I'm giving him fresh veggies as well as bug bites, catfish pellets and a wafer. He goes through cucumber and squash rounds in about an hour and I give him the veggies twice a day. I'm not entirely confident about how much I'm feeding him. The advice I've found doesn't mention the fish's size.