any good coldwater fish?

I personally love coldwater-subtropical fish. Here are some options of fish that will not need heaters (or you could always add one if you want more fish options)

Alot of coldwater (true coldwater) species are messy large fish needing loads of oxygen.

Goldfish

Fanch goldfish are loverly fish needing 20 gallons each but 20 then an added 10 for each is ok.

Common need 40 minimum each.

Comet need 30 minimum each.

Shubunkin need ponds.

The smallest breed of goldfish is a pearl scale fancy- beautiful fish.

Goldfish grow large and messy so they need big tanks and twice to triple filtration capacity. But in return live over 10 years and have great personalities. (They also need air pumps with loads of oxygen being pumped into the water). It is actually bad for goldfish to be in hot temperatures.

Weather loach

They need atleast 50 gallons, grow 12 inches and prefer to be in groups. Great fish, funny to watch. (They jump!)

Hong kong pleco

Only get 3 inches most, 2 more common. Need fast flow from a powerhead and filtration. Not long lived at all and hard to keep in communities.

White cloud mountain minnows

Great little fish, subtropical but are best in cooler temps of about 18-20. Need to be in 6+ groups in 15 gallon + tanks. Very peaceful.

Barbs

Golden- up to 3 inches, need atleast 20 gallon

Rosy- up to 3 inches, need atleast 20-30 gallon

Barbs need to be in shoals of 6+ and tend to nip fins if not in groups. Hardy and great to watch in groups. Need same temps as minnows.

Taiwan bitterlings

Up to 3-4 inches. Need 30+ gallon tanks. Beautiful fish. Can nip fins.

Paradise fish

Up to 4 inches. HIGHLY agressive, do not mix with any fish. Colourful with characters but solitary.

Hope this helps =)

Need to know the aquarium size.

Goldfish are fine on cooler water, mine have lived for years with a little bit of ice on the pond in winter, hope your house is not that cold!! But Goldfish need large tanks as they are big messy fish.

White Cloud minnows are another good coldwater fish, they only grow to a bit over 1" long, so are happy in a school in a 10gal tank.

Otherwise, get a tank heater, then the room temp doesn't matter and you have a wide range of smaller tropical fish.

Ian

1. Tail size has noting to do with it. 2. All animals breed 3. They are more likely to breed in a pond environment 4. Natives, phalloceros caudimaculatus, white cloud mountain minnows, paradise fish.

What size is your tank? can't really recomend fish without knowing a tank size

You could always get a tank heater...

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fancy guppies aren't the greatest choice, feeder guppies would work though.

Goldfish, though 20 gallon tank for it.

White cloud minnows, these are beautiful little fish and have a lot of potential if you get a large school going.

Hillstream Loach

Some barbs.

just get a heater and get other fish like guppies mollies and they will breed and make more fish

White Clouds, goldfish, paradise fish all make good cold water fish. If you get paradise fish and white clouds that would be a good display as well. You could also buy dojo loaches.

any goldfish breed will do