Goldfish

[joeysgreen]

Hello, my son Anthony has 11 goldfish in a 20 gallon tank. They are growing bigger. What size of an enclosure would be good for them?

Thanks kindly,

Ian

[Ichthyosporidium]

If you go with what I've always thought for the minimum volume for goldfish is as follows:

2 Gal. (7.56L) of water per inch of fish (base of tail to tip of the snout).

10" average for adult size.

Account for substrate, ornaments, equipment, plants, etc. an average to me is best seen as a liberal 20% of the total volume so add that on to the total.

so the formula in this case is: 10 X 11 X 2

= 220 Gal. (831.6L)

220 X 1.2

=264 Gal. (997.92L) total

Either a big aquarium or a nice do it yourself project for spring...a pond.

[Ishkabod]

Not to contradict but my rule is 1 inch per 5 gallons because goldfish like to grow so that gives you some wiggle room to find a bigger or better home for them as they grow. For that many fish you will eventually need a pond if you plan to keep them or a really really big tank unless you have those fancy tail weird big belley and head/eyes types. One way to stretch the length of time you can keep those fish in that tank is to feed them a higher quality food like NLS. They need less food and produce less waste that way and thus the water gets poluted less and that means fewer water changes. If they are regular golfish that will grow those 10 inches then the rule of 1 inch per 2 gallons for their final size COMBINED with NLS is a good amount just be sure to do weekly water changes as goldfish are more sensitive to Nitrates than most other fish.

Now I'm in your situation but with only one fish and that is my Koi. He/she's 11 inches in a 40gallon tank. If it weren't for the fact that i expect another 3 or more inches growth in the next 2 months and the tank is only 12 inches wide thus making it hard for it to turn around i would push it a little longer but that won't wash this time.

Good luck and don't throw in the towel yet If you want i'm sure there are lots of tips that might help and info on how fast they reach that size and how to make keeping a bigger tank easier and you never know when you might come across a deal in that time for a bigger tank and stuff(the bigger the easier in my experience)

L

If you go with what I've always thought for the minimum volume for goldfish is as follows:

2 Gal. (7.56L) of water per inch of fish (base of tail to tip of the snout).

10" average for adult size.

Account for substrate, ornaments, equipment, plants, etc. an average to me is best seen as a liberal 20% of the total volume so add that on to the total.

so the formula in this case is: 10 X 11 X 2

= 220 Gal. (831.6L)

220 X 1.2

=264 Gal. (997.92L) total

Either a big aquarium or a nice do it yourself project for spring...a pond.

Edited March 14, 2010 by Ishkabod

[Crystal]

All of my goldfish (common feederfish) grew past 10" within 3 years... They were about 15" when I gave them away (they now live in someone's dugout), and still growing. I had a 300g pond for them.

You could consider an indoor pond (if the family won't murder you).

I found 5+ gallons per inch of goldfish to be best, as they are deep-bodied fish (there is a bit of difference between 1" of tetra and 1" of goldfish).