# Do goldfish stop growing after a certain age? **URL:** \ **Category:** Factual Questions\ **Created:** [December 15, 2004, 6:01am UTC](https://boards.straightdope.com/t/do-goldfish-stop-growing-after-a-certain-age/279935 "2004-12-15T06:01:39Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [December 15, 2004, 6:01am UTC](https://boards.straightdope.com/t/do-goldfish-stop-growing-after-a-certain-age/279935/1 "2004-12-15T06:01:39Z")
I’ve read more than once that goldfish will grow as big as their tank lets them…but do they become “full-grown” after a certain age like people do and a small tank stunts their growth, or would they get bigger in a bigger tank at any point during their life? (I’m thinking specifically of comets.) ---
**Author:** ![Seven](https://avatars.discourse-cdn.com/v4/letter/s/3d9bf3/32.png) [@Seven](https://boards.straightdope.com/u/Seven)\ **Post date:** [December 15, 2004, 6:38am UTC](https://boards.straightdope.com/t/do-goldfish-stop-growing-after-a-certain-age/279935/2 "2004-12-15T06:38:08Z")
I think the problem with tank size is the bigger the fish the more waste. The more waste in the water the more unhealthy the fish becomes. Unhealthy fish = stunted growth. Most of the comet type goldfish I’ve had lived many-many years and got to be 5-6 inches in size. Some even bigger. This is in pond and large tank enviroments. Their main growth slows in about 3-4 years. They continue gaining some bulk for several years after. Their lifespan is about 15-20 years in prime enviroments. I think the oldest recorded was around 40 years old. Kind of seems sad when people put the little guys in bowls and they die 3 weeks later. Oddly, for such a dirty fish, unfiltered 1 gallon fish bowls are the WORSE place to keep them.