The Problem About Goldfish.

[Tokis-Phoenix]

So, today i was thinking about goldfish. Often you read you need 20gals for the first goldfish and 10gallons for everyone after that- sounds fair enough i suppose. But isn't this a bit vague, like so much of the other info on the internet on goldfish, considering how many varieties of goldfish there are and how much they vary in size and requirements?

Info on goldfish types, sizes, temps etc;

http/www.petstation.com/goldfish-varieties.html

http/www.####ftypes.html

These two sites for example seem to contradict each other- one says common goldfish grow to 8inchs+, while the other says 14inches. Big difference. So who's telling the truth?
And is it just me, but does 30gallons minimum sound quite excessive for somthing like pair of 4inch fantails, but far too small for a pair of comets that could potentially get to 14inchs long according to some sites? I think we need to review the "20gallon for the first goldie, 10gals for every one after that" rule of thumb . People would freak if you kept 2 10inch common plecs in a 30gal.
I feel like we have just gone from bowl-fish to vague-fish with goldfish.

 

[The-Wolf]

IME
the term goldfish is generaly refering to common goldfish/shubunkins, comets and other torpedo shaped carp varients, not fancy goldfish.
fancys have their own considerations like higher temps etc.

 

[RandomWiktor]

I agree. 30 gallons, I can tell you from personal experience, is simply not adequate for common goldfish. I have a 75g tank with two commons, and I fear that even it will not be large enough in the long run. Common goldfish are much like their ancestors; they can often grow to nearly two feet in length given good nutrition and adequate housing. They are better kept in ponds, as it is really the only way you can have commons for the entirety of their 20+ year lifespan, and keep them as nature intended - in the company of other fish.

However, I disagree that 30 gallons is excessive for fancy goldfish. Yes, when they are young, it seems like a massive amount of space, though frankly for an animal who is forced to live in one small space its whole life, I believe fish ought to be permitted to enjoy such a space while they are still small and young enough to enjoy it. But even fancies, with age, can reach close to a foot in length (I believe this site suggests most reach about 10in). Someone posted pictures here a while ago of a lionhead whose head was as large as a fullgrown Koi's; just because fancies are short in body doesn't mean they produce any less ammonia, so it is well advised to keep them in quarters much larger than you would comparably sized tropical fish.

I think the information on this site regarding goldfish should be changed so that the 20 gallon and 10 per additional fish applies only to fancies. Regarding commons and comets, it should really suggest larger quarters, and caution about how large these fish become at maturity. Furthermore, it might benefit fish if we point out that young fancies can be kept in smaller quarters until they are larger. Many people are immediately discouraged when they think of having, as you pointed out, a few four inch fish in a massive tank. So long as water quality and growth are carefully monitored, young fancies could probably be kept in something smaller and likenable to a "grow-out tank" until they are better suited for larger quarters. This may encourage people to heed by proper goldfish husbandry rules more closely, as it makes the firm stance on tank size seem a bit more reasonable.

What's more, we could use some kind of guide to filtration for goldfish. Goldfish do indeed need large tanks because of their large size and high waste output, but equally important is good filtration; the biggest tank in the world will not suffice if the filtration is lousy. Goldfish NEED to be in cycled tanks, NEED filtration that far exceeds the tank size, and NEED to be kept very clean. Without those key elements, reccomendations for proper tank size quickly become useless.

 

[Tokis-Phoenix]

Considering different types of goldfish grow to different sizes, we should give each type the amount of gallons really advised to keep it rather than applying the same rules to every goldfish.
75gallons sounds far more appropriate for comet goldfish than 30gallons though- i think we need to find out the real max sizes for goldfish as well as there are so many sites on goldfish on the internet that contradict each other.
A couple of months ago i adopted a common and comet goldfish, currently they are in a 30gal and have already grown a couple of inches and are very active. I'm building a pond for them in june, where i hope they'll continue to grow although i was told by the previous owner they could be anything between 2 and 15 years old (he couldn't remember when i bought them, although said he hadn't bought any new fish in the last 2yrs).
I've already decided myself they are too big and active for the 30gal tank.

 

[black angel]

Im of the opinion that slim bodied goldfish should not be kept in aquariums at all, unless in a zoo where the adequate filtration and size of tank will be appropriate for them.
For fancy goldfish i think it depends on the size of the fish when you buy it and if you are prepared to upgrade through its life.
For me 10 gallons is enough for up to 3 body inch of fish and then moving up tank sizes as the fish grows.
As for adult size of goldfish types then no two fish grow to the same length.
Ive seen adult goldfish at 5 inches and some at over a foot and blackmoors at 6 inches and 12 inches.
Good filtration also plays a big part in the health of any fish and particularly goldies which can excrete 30% of their body weight per day in ammonia.

 

[Tokis-Phoenix]

No i think slim bodied goldfish can still make good aquarium fish, i just think we need to advise bigger tanks for them. Sailfin plecs can grow up to 2ft long and need a 125gal tank(or a tank at least 5ft long and 2ft wide) and are big waste producing fish. They may lack the activity a comet goldfish has but i think 125gal tank would be a good size for a pair or trio of comets- people keep trio's of bala sharks in tanks that size and they grow to the same sort of size as comet goldfish and are active fish.

 

[Iron Man]

I don't know where they'd get that a common only gets to 8 inches. I've had a couple of fancys get to 8 inches.

Personal experience tells me that the "torpedo" shaped goldies should be kept in ponds, not tanks. Though they may not produce much more ammonia, they need much more swimming space and they are more "coldwater" than the fancies. Keeping a few of them in something like 125 gallons....I don't know.

10 gallons is possible for 1 baby/medium fancy goldie, before it grows up....sure. But he will need companions. I would never keep one alone...so a 10 gallon would just be out for one IMO....and I would NEVER ever ever cycle such a small tank with a medium goldfish. You'll either kill it or scar it for life.


Having had experience with the fancy variety for quite some time I can tell you that 30 gallons might seem excessive for only a pair if you've never kept goldfish, but trust me it isn't. These fish produce A LOT of ammonia. You will need good filtration even with only two in a 30 gallon.

Also, these fish can experience boredom. They need some space to explore, plenty of plants (plastic, they will eat any and all live plants), substrate, and unlike most other fish....they need light. If you keep these fish from light they will lose all of their body color and its my belief that due to a lack of any or all of the above they can actually experience depression.

All that being said....get you a 30 gallon and a pair of fancies and never look back.