I have a rubber lip plecostomus, and a comet goldfish. What size tank should I be getting for them?

drferox:

A big one.

There are plenty of better resources out there for fishkeeping than me. There’s all of fishblr and numerous online forums, and it’s worth joining at least one to help you out in your early days. I am not into fish enough right now to help you.

75 gallons, bare minimum, with very frequent water changes. Comet goldfish get huge.