Filter plus air pump?

[Bruce]

I have a filter that’s also a fountain. Do i still need an air pump for oxygen or the fountain will suffice? I plan to put maybe 6 kois. I have about 250 gallon pond

 

[combatwombat]

That fountain is more than sufficient for a
250 gallon pond, but 250 gallons is far too small for 6 koi. It’s really on the brink of too small for even 1 koi. You can raise a few beautiful shubunkins/comets in there, though.

 

[GBBUDD]

250 gallon is ok for 6 gold fish but koi will out grow that in 3 years and thats major league pushing it

 

[Bruce]

Ok i did not think about growth lol. I recalculated and it’s about 320 gal. Anyway good point. I wanted kois to also get rid of mosquitoes. Gold fish and other tropical fish also eat insects? I’m ok to put colorful goldfish and may be guppies too

 

[j.w]

@Bruce
Yes for sure goldfish and Shubunkins ( a type of calico spotted koi looking goldfish) will both eat mosquito's. Shubunkins are very pretty, some even have long flowing tails. You can find them at pet shops or fish breeders. Most any fish will eat the bugs!

Shubunkin's

 

[poconojoe]

If I were to start all over, I'd opt for shubunkin rather than koi. I do have both and lots of goldfish too.

We have this discussion all the time. The words "koi pond" are used universally for a garden pond. Because of this, most people don't realize how much water a koi needs or how much waste they produce.

They need a lot of swimming room and adequate filtration.

 

[Mmathis]

Hello, Bruce! It’s already been said — please rethink the koi. For goldfish, that set-up should be fine, but depending on your climate and whether the pond is in full sun, you just need to watch your water quality to decide if you need more water movement at some point.

 

[poconojoe]

I will also note that it can sometimes be harder to keep a small pond than a larger one. Parameters or water quality can change very quickly due to the small amount of water.
Therefore you will need to pay more attention to these things.
A good pond water test kit should be used to keep an eye on the parameters. The type with liquid reagents is preferable to the type with test strips. The test strip tend to be inaccurate.