A friend of mine has a common pleco that she got for her kid back in the day, having no idea how big they get. He's about 5 inches long now and she doesn't know what to do with him, she has him in a 15 gallon. She's offered him to me and I've always wanted a big ol' common pleco have never gotten one but I didn't think i could house him as an adult. What size tank would you need to keep them together as adults? I don't really want other cichlids, I have an african cichlid tank already, which I love, but I want something different for this tank (yes I realize Oscars are cichlids, but they look so different from my Africans they feel like a different fish to me, not more of the same).