30g for a comet?


Large Fish
Jan 9, 2011
New England
my poor comet is temp living in a small (1.5g?, several water changes over the course of 2 weeks, weekly testing...ssmall - 3g capacity - filter to help with the poor conditions of such a small space) bowl until I can get my reptile room situated with the proper shelving that can also hold the tanks, or until I can make enough space for having 3 tank stands in there. Anyway, my question is: how long would the 30g be ok for a comet that is currently about 1.5"?

also, I really dislike the look of fake plants... what kinds of real plants would be good for him that he can't eat too readily (I'm resigning myself to thee fact that I will need to re-stock the plants often, so I will likely have a planted tank for just this reason)


Oct 29, 2010
Well, a comet goldfish can grow to be a foot long, so it's up to you to gauge how large he can be while still having good water quality and quality of life.

I'm not sure how long it takes a fish to grow that large.

Anubias are supposed to be one of the few goldies won't eat, although he may rip them up. They come in many different shapes and sizes :)

Way to go getting your fish a bigger tank :D He'll love having the thirty gallons to himself at this size!


Superstar Fish
Jun 25, 2003
Leduc, AB, Canada
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My comet golidies have maxed out to about 8" now after 8 years. A 30 gallon with strong filtration should be fine so long as you don't get too tempted to add too many more fish.

There really is no such thing as 'too big' for the fish. Too small is more a matter of fish heath and proper growth... as well as harder to maintain in terms of water quality, than larger tanks.

Comets are the most fun to have in bigger tanks.. thats the sad part other enthusiasts often miss... they never see a fully functional, healthy, active, well proportioned goldfish at its best. Give the fish as much space as you can afford and you will get the most out of your fish enjoyment as a result.