How Are These Goldfish Still Alive?

[Manic Fury]

I'm home for Thanksgiving and my Aunt has a 29 gallon fish tank with 4 fancy goldfish in it and a sucker fish. No air stone. A 20-40 gallon filter. I don't think she uses dechlorinator.

I know that you're supposed to have at least a 90 gallon tank for that many goldfish.

Just wondering how/why these fish are able to live. They all seem happy and healthy. No signs of stress or illness.

Picture related.

 

[matthew_raw]

Goldfish are quite hardy but thats pushing it, atleast there is a filter, i have seen higher stocked tanks with no filtration. There must be a good coloney of bb in her filter then haha

 

[Manic Fury]

Must be. I asked her how long she's had them and she said about 5 years. I was in shock. I couldn't keep my 1 goldfish alive in a 10 gallon tank for more than 3 weeks when I first started out.

Unbelievable. These fish must be gods. Haha

 

[pip walters]

Clearly, the filter is very capable.
Goldfish are far tougher than you may think - they have survived 100s of years of domestication, so they tolerate a wide range of conditions. They are related to crucian carp that can tolerate zero oxygen for many weeks under the right conditions by producing a kind of natural anaesthetic! It is thought that crucian carp (Carassius carassius) were used in the production of coloured fish from the wild goldfish Carassius auratus

 

[matthew_raw]

Maybe she got the capacity of the filter wrong when she told you. She may have massivley overfitered tank, either way goldfish have a huge bio load, the tank looks clean tho. Does she have any live plants or do water changes?

 

[Manic Fury]

I checked the filter and it's the standard amount for that tank. She said she doesn't do water changes except for once a month.

I dunno. Maybe everything is fine. It just amazes me!

 

[matthew_raw]

Sometimes its all okay sometimes its not? Hope they do well in the long run nice fish !