I have a feeder goldfish that my son dubbed "Orange Bacon". We have had him for about 2mo now, and he seems to be very active & healthy.... Even greets everyone in sight at the front corner of his tank (it's triangular), at any given time, like he's starving!! He/she is a bit of a pig tho, and I have 2 watch that my hubby & son don't feed him again if he's already been fed. We used 2 have a calico fan-tail, Captain Jack, that was accidentally killed w/ kindness, by my inexperienced fishkeeper hubby
I'm sure if u decide 2 get some, feeder fish will be just as nice a tank addition as the more expensive goldfish! As with any new fish, monitor them closely & treat immediately if u see any signs of disease. Good luck with ur new venture!!