My son's self-sim is lonely without his own pet goldfish.
My son's RL goldfish is all white, and is named Bubble. She's a Ryukin goldfish.
Here's a good reference for her bodyshape:
http://www.petgoldfish.net/ryukin-goldfish.htmlHere's a reference to what her coloring is like:
http://www.petgoldfish.net/comet-goldfish.htmlAlso, could you do some bettas?
If need be, a fishbowl that isn't interactive is ok, too.