Hmm.. fishies... Well, the goldbulbs are certainly a good start, and both anon and Barbara have excellent ideas I wish I could remember which fish I bred last time I restarted... I think it was a spotanus, but I can't remember what fin type... maybe it was orange... worth a bit more than the golden goldbulb, as far as I can recall. Anywho, you can either keep breeding the fish you used to get the goldbulb, or keep a pair of goldbulbs themselves. I would do the latter, because you can breed them all together to get a tank-full of goldbulbs, and then sell all but two, versus getting only two fish at a time from your original breeding pair ^_^