Hypothetically, a man has a single fantail goldfish. He has a 20 gallon tank that is 30 " long. He sees fish is timid and wants to get him two friends to make him feel better, but rule of thumbs indicate a need for a larger tank to do this. No larger tank will be forthcoming (for several years). What does he do?

What do you think? 3 crowded fish or 1 lonely fish? The one fish is about 2".

Hypothetically, he does 50% water changes weekly.

In my humble opinion, keeping him alone would be better. Of course there is the question of cleanliness, but the bigger issue is space. Goldfish usually need a lot of space to swim around, and putting more than one in a 20 gallon might cause bigger issues than loneliness, such as aggression and stress.

However, if "this man" decides to go with the idea of multiple fish anyway, he should only get one more. Goldfish are not schooling fish, so there's no need to keep a specific number. He would have to make sure there are plenty of plants for them to hide in. The more, the better.

Hypothetically, of course. ;)

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Creatures great and small, I love 'em all! But mainly the fish.

maybe a few white clouds? 2 or 3 white clouds will add much less bio load or waste than just one more goldfish. make sure any tank mates can survive in cooler waters.

Bad idea... Are you talking about white cloud tetras? For one thing, they can NOT tolerate the colder temperatures that goldfish thrive in. No tropical fish can; that's why goldfish are kept only with other goldfish. For another, they're so small that as soon as the goldfish grows big enough (and it will), they'll become dinner.

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Creatures great and small, I love 'em all! But mainly the fish.

I am assuming he means white cloud mountain minnows (currently what I am looking after) as they can survive in cooler water, but they only grow to about 1.5". But as stated the goldfish will probably eat them, it even says so in this article

White Cloud Mountain Minnow - Tanichthys alboneubes

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Welcome to the board. Maybe keep an eye out for a bigger tank used?

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"Being ignorant is not so much a Shame, as being unwilling to learn".-- Benjamin Franklin

The hypothetical man lives in his hypothetical father in law's house, where, hypothetically, aquariums are not allowed.

Hypothetically, a 20 gallon tank is under the radar enough to slide; much larger and the hypothetical man will hypothetically be out of the home.


PS. The hypothetical man is real. And he's me. Thanks for the replies.

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