To answer yer other question, no, they dont really bite, Since their mouthes are located below them, they are more meant for bottom feeding, and their coloration is their largest defense. They are extremely docile, but also hard to get to eat. I hatched one, but mine never ate, and it wouldnt've of survived in the 55 anyway. You have to bring that hing back man, get a large tank, get proper filtration, do more research here, know wat yer doing, and not rush into things. It is also easiest for you to just buy a sump off of ---- or smthing. They come all setup with pumps and overflows, bioballs and even built in skimmers for only like $180-$200, which is a DEAL if u ask me. For a 125? You need some serious filtration, Then u will need a uv probably for disease and water clarity purposes. Taking the necessary precautions is key in this hobby, and if you dont, then things can get disastrous. And imo, you should have a lot more lr in yer tank. Dont mean any harm btw, only trying to help.