Since its been several weeks that hes been stuck in that .5 gallon, I assume with a lack of proper water changes or aeration,....its possible he may not survive too long, even if he was transferred into idea conditions tomorrow. The damage may very well already be done....though these guys can be hardy. It all depends, its hard to say.
You could always check a local store or two anyway and see if they may be willing to take him anyway? I don't know if the big chains do it, but I know sometimes local stores will take fish for store credit.
Any chance you could ask around/advertise and see if someone in your area might have a large enough tank that may want him?
i had a common pleco in a 29 gallon for over 10 years. not perfect conditions at all, but that alone should tell you how long they can live. he was well over a foot long, too. :I poor little guy you got... some pet stores will take random fish for in-store credit. my local pet store does. they ALWAYS get huge Oscars and goldfish. had an arowana once. beautiful, but super scary looking fish.
That poor thing. The conditions the Pleco is being kept in makes me sick.
Try searching for local fish stores in your area online. Hopefully you will find more than one. Either you or your friend can call around and ask if one would be willing to rescue/take him in. Often times the local fish stores will take in fish needing new homes.
I just want to clarify to everyone that she just got into fish keeping. She wasn't told about how big he could be. I've already brought up the issue of being in a small tank hence why there is only ONE there now, not the three. I thought tha the pleco was already full grown, and I told her that it might need at least 5-10 gallons. This is partially my fault as well.
I just let her know about how big plecos can get. What she chooses to do is up to her. If she doesn't want to bring it back to the pet store, then I'll adopt the little guy for a bit, give him some room and a nice tank now, and once he gets big and strong enough, I'll do my work.