have just added a small filter to his dinky little tank,with media from my other tanks filter in it. hes loving the water movement,much more active little guy.
I'm guessing he's probably stunted from being kept in such a small tank for so long. There should be lots of information on stunting in the coldwater forum here.If he survives the next few weeks, get the biggest tank you can afford. 55 gallons would be good for 2 or no more than 3 regular shaped goldfish. Fancy goldfish can get 6 inches long or so, common or comet goldfish can get about 12 inches long. If you get him another goldfish as a buddy, it should be one with a similar body type. Common and comet goldfish swim faster than fancies and would get all the food first. http://www.craigslist.org/ is a good place to look for used tanks. It's classified ads and you can look just in your local area. Both of our 55's came from Craig's List and were less than half the price of new. Try looking both under pets and under general, where they tend to get overlooked.
2 of our 3 goldfish were rescues from a really yucky tank. The owner had started with 8 or 9 in a 20 gallon tank with a 10 gallon filter. When we got them, the water was the color of pale iced tea and the 2 remaining goldfish were brown and not even shiny! 8 months later, they've grown from about 1 1/2 inches to about 4, and both turned orange, but it took one of them about 6 months to change color. We accidently broke the tank getting them home and didn't have any other tanks running at the time, so they had to start over with all new everything and survived anyway. Good luck to you and your new fish!
thank you for your help,hes still looking good,very active,hes stuck in this teeny tank until 1st week of april,and we will be buying a 30 gallon i think,so hes not got too much longer being stuck in his tiny home. wish i could afford one now but unfortunately i gave away our other 3ft tank last year,now i wish i hadnt as we wont have any money until end of march!