Goldfish Selection

Briggan

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Hi!
I have heard/read a lot of conflicting info about keeping different types of goldfish, mainly on the minimum and proper tank size.
So I would like to ask:
What is the minimum tank size for 1 fancy goldfish?
Long, standard, or high tanks?
What is the best temperature?
Any info is appreciated, I trust this site more than others :)
Thanks!
 
The minimum size tank for any goldfish is 4 foot long. This size tank is big enough to keep the goldfish until it is an adult. If you have 1 small fantail goldfish, it can live in a 2 foot tank for a while but will eventually need a bigger home.

Tanks that are long and wide are better for all fish because they have more swimming room (left and right). Fish only swim up and down to get food from the surface, and surface area (length x width) is much more important than height.

A nice sized tank for fancy/ fantail goldfish is 4 foot long x 18 inches wide x 18 inches high. If the tank is wider or longer, that is even better.

Single tailed goldfish grow bigger than fantail (2 tails) goldfish and a tank that is 6 foot long x 2 foot wide x 18 inches high is suitable. A 6ft x 2ft x 2ft is even better.

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Goldfish are coldwater fish but can also live in warm water. They will survive temperatures down to just above freezing, and up to 30C or more. This does not mean they can go from 5C to 30C instantly, but they can survive in those conditions if the temperature changes slowly over a period of months, like in the wild when a river cools in winter and eventually freezes over.

Single tailed goldfish tolerate cold conditions better than fancy fantail goldfish. I prefer to keep the fancy fantail goldfish at temperatures between 15-25C. Single tailed goldfish also do well in these temperatures.

Fish kept in cooler water should be fed less often because they take longer to digest the food.

If you want to breed goldfish, you keep them in cold water for a couple of months and then slowly raise the temperature. When the water temperature gets to 18C or above, the fish will start breeding.

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Goldfish need plant matter in their diet. Duckweed is a small floating plant that is readily eaten. They will also eat any soft leaf aquarium plants.
 
I have a black moor goldfish that i had in a 690L system in a 5ft long tank. I have actually downgraded him to a 160-170L tank, it's 4ft long but not very tall. He is not an active swimmer so he does very well in that tank. From keeping Fancy Goldfish my first bit of advice is not to get fancy goldfish, haha. I love my black moor but i won't be getting him a friend or get any more in the future.

I'd say the minimum for ONE fancy would be 150L but long tanks over short and tall ones.
 
Rule of thumb, at least in the US, is 20G for first fancy and 10G for each additional. Single tail goldfish need 100G for one fish. This is, of course, adult fish. High tanks are better for goldies as they explore the entire tank. Ideal temp is 65 - 70F. My tanks stay at about 72F and are fine. Good luck!
 
Thank you!
I was thinking of getting a fancy, not sure what kind, maybe a black moor? If the room the tank is located in stays around 70 degrees f. on a normal day and is not in direct sunlight, is a heater necessary? I have one on hand, just in case. Also, I read goldfish need lots of oxygen. Would a waterfall filter provide enough surface agitation or is an air stone/bubbler needed?
Thanks!
 
You don't need an aquarium heater for goldfish in a house. Average room temperature for people is fine for the fish.

Have an airstone bubbling in the tank.
 
Thanks!
I think this will be my next fish after I've prepared the tank. Thank you for your information and help!
 
I have both an air stone and waterfall filter. My Goldie’s are adults though and one is over 8” long. Goldies will eat most plants so use Amazon sword and Anubias in your tank. No heater needed. Have fun!
 
Thanks! Do you recommend floating plants if you have a waterfall filter? Also, in general, is there any one type of goldfish best suited for a 20 gal more than others? I really like the black moors but I would just like to check because they seem more of a hefty fish.
Thanks again!
 
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Also, in general, is there any one type of goldfish best suited for a 20 gal more than others?
Fancy fantail goldfish are a better choice than single tailed fish for small tanks.

The single tailed fish are faster swimmers and much more active, whereas the fantails don't swim as much or as fast.
 
One black moor would work fine in a 30G. However, goldies are companion fish and would be happier with a friend. One in a 29 is doable though. Black Moor’s are my favorite! Keep in mind though that they often turn gold as they age.
 
Oh, I forgot about the floating plants. So my females eat anacharis but my males leave it alone. I just often float it in my tanks. The males have had a big bunch for about 6 weeks. The girls just have about 10 stems left. They don’t eat hornwort as much but it is so messy! Try the anacharis. I find it does better floating that burying it.
 

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