TailSpin

I'm thinking of getting a few gold fishes in to my 55 gallon tank. I have had an oscar for 4 years in there, it grew to 12 inches and 4 days ago it jumped out. My water: pH-7.5, Kh- 4 and temp. 80F,(nitrate-10 nitrite-0) is this ok? How many fish can i put in to the tank concidering their adult size of 12 inches and their waste output? Once again since i had an oscar, do yoou think bacteria will be able to handle ammount of waste from lets say 3 adult goldfish? Thank you in advence.

0morrokh

The "goldfish" that you are talking about are probably koi, which do get to be about 12" long. Three adult koi might be okay in a 55 gallon, providing you have good filtering and are careful not to overfeed. If you want more fish, most goldfish are actually 1/2 or 1/3 of that size. And you don't need the heater--goldfish and koi like cool water, although they'll be fone at 80 degrees.

fletch

Gold fish can get to 18inches and koi can get to 3feet. Generally go by the rule of 1" of fish to 1 gallon of water. Add up the average size your fish may get and if its below 55 your fine.