Tank size for common/comet goldfish

[DustinJWagner]

Hey everyone!

Curious to gather thoughts on tank size requirements for the standard common/comet goldfish. I am planning a 125 gallon and am wondering how many I should select. There is quite a range of opinions on various sites and forums. What seems to be the general consensus? Thanks. :)

[mynameisnobody]

@DustinJWagner the answers will vary depending on filtration, feeding schedule, water change schedule, and use of plants. Also size will dramatically effect this. If you are housing for life, personally I wouldn’t add more than 3-5. The more you keep, the more maintenance you’ll have to do for water quality. The great news is that commons and comets, although they get larger than fancies, they also are definitely much more hardy and durable. Your room for error is pretty high with these fish. However, it’s a living thing so I wouldn’t push it too hard. Hope this helps

[DustinJWagner]

On 2/12/2023 at 9:28 PM, mynameisnobody said:

@DustinJWagner the answers will vary depending on filtration, feeding schedule, water change schedule, and use of plants. Also size will dramatically effect this. If you are housing for life, personally I wouldn’t add more than 3-5. The more you keep, the more maintenance you’ll have to do for water quality. The great news is that commons and comets, although they get larger than fancies, they also are definitely much more hardy and durable. Your room for error is pretty high with these fish. However, it’s a living thing so I wouldn’t push it too hard. Hope this helps

Thanks for your thoughts!

[arjin101]

Goldfish can be considered "dirty" as long as you have good filtration, do your weekly maintenance you should be able to keep 3-4 in a tank that size when they are full grown.  Depending on your maintenance regimen and how much filtration (not to be confused with water flow) you could keep more. My suggestion is let your skills decide and if you are not opposed to rehoming start with a few more and grow let them grow into it.  4 2-inch fish in 125 looks kinda barren and leads to "oh I can add a few more" then you run into a tank filled with 50 fish and not willing to get rid of any.  (What? Me? No, I never did anything like that, I don't know what you're talking about)

[DustinJWagner]

On 2/13/2023 at 6:45 AM, arjin101 said:

Goldfish can be considered "dirty" as long as you have good filtration, do your weekly maintenance you should be able to keep 3-4 in a tank that size when they are full grown.  Depending on your maintenance regimen and how much filtration (not to be confused with water flow) you could keep more. My suggestion is let your skills decide and if you are not opposed to rehoming start with a few more and grow let them grow into it.  4 2-inch fish in 125 looks kinda barren and leads to "oh I can add a few more" then you run into a tank filled with 50 fish and not willing to get rid of any.  (What? Me? No, I never did anything like that, I don't know what you're talking about)

Thanks! That definitely makes sense. I can totally relate haha some fish look so  tiny and silly in a big tank but they don’t always stay that way!!

[Flumpweesel]

I had two in 60 both fish pushing about a ft long.  One canister and one internal power filter.

Water changes were about 20 percent every 3 to 4 weeks.

Given you're going twice as big I'd guess at 5 to 6 fish but while that will look like nothing when they are tiny will soon seem full as they fill out.