Large Old Goldfish

by Isn
(Dundee..Scottland)

Hi there, our old goldfish who lives in our pond alone now, continues to grow, however in warm weather he sits at the top of the water, almost as if he’s sunbathing, is this ok?

He must be around 15 years old now, also we though about putting a few other fish in to keep him company, do you think that’s a good idea?

Thanks

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Grant's Reply

Hi Isn

Sunbathing is exactly what your Goldfish is doing.

He has just come out of hibernation, or a period of low activity, and is taking advantage of any sunlight he can get. Like most animals, Goldfish are healthier if they are exposed to sunlight.

15 years isn't old for a pond fish that has been well looked after. 25+ years isn't uncommon.

To answer you question concerning companions, yes Goldfish do prefer the company of other Goldfish but, and it is a large but, if you want to add more fish to an existing eco-system, you need to consider the impact even a few new fish will have.

Firstly the fish have to be compatible. If your existing fish is a single tailed variety, only single tailed fish should be put in with him.

They should be a reasonable size otherwise they will be considered as food by the larger fish.

Any new fish should be quarantined for at least two weeks, preferably four before being introduced into the pond as the pond has been a closed system for some time and your old fish may not have immunity to any new diseases that the new fish could be carrying.

The last thing to consider is can the eco-system support more fish?

Having a large, old fish that is continuing to grow tells me his environment must be very good.

If you add more fish, more food will need to be fed, causing more bio-load. If the pond isn't filtered, this bio-load (waste) needs to be processed by the existing eco-system.

I don't want to put you off getting a companion or two for your fish, but because adding more fish to the pond changes the present eco-system, be prepared for changes that may occur, such as the water going green with an algal bloom, or the water quality dropping, especially during the hotter summer months.

I would start with just one extra fish first, and monitor how the pond adjusts to this fish over the summer months.

If the fish grows, and water quality doesn't drop to a dangerous level, you can assume the present eco-system can handle the extra fish.

Also consider that as fish grow, they are increasing the bio-load on the pond.