Lazy Koi. Is this normal?

[Craig Brown]

This is my first summer with my Koi. I have two ponds (the same water flows through both). Pond 1 is approx. 1600 gallons. It contains 10 Koi that range in size from 8” to one at 20”.

Pond 2 is about 300 gallons. In that I have approx. 15 small koi (a few inches in length).

Water tests are OK. The PH is about 7.8. Very little ammonia or nitites. Nitrates are high though less than 40. I treat this with water changes. I also have a lot of plants including a small pond (about 100 gallons) that is all Water Hyacinths.

Aeration: I have a waterfall filter as well as two air stones with a powerful air pump.

Behavior: The big fish (pond 1) don’t seem to swim much. They lay together with their bellies close to the bottom. Or they hide under the plants and I would guess do the same thing.

The little fish (pond 2, same water) swim constantly.

After many “newbie” issues, the water is finally clear. I think they were more active earlier in the summer but the water was too brown (then green) to tell.

Is this normal Koi behavior or am I missing something?

Thanks!

 

[sissy]

They may be trying to stay cool .I always put shade over my pond in the summer .Koi don't seem to like warmer water .I also provide air with my 12 port laguna aerator .

 

[sissy]

it may help the bigger they are the more oxygen they need .

 

[Tula]

Is your waterfall filter, the only filtration for your ponds?

 

[Mmathis]

Personally, I think they don't have enough room and they might just feel cramped for space. Or starting to show signs of illness.

Pond 1 is 1600 gals and contains 10 koi ranging from 8" to 20". That in itself is very small space for that many koi. Pond 2 is 300 gals with 15 koi. Again, small space, even for that many if they were goldfish.

That means you have 25 koi in less than 2000 gals of water, separated into connecting ponds. Even with decent water parameters, that is a set-up for illness. Are you noticing any other unusual behaviors with any of the fish? Are any flashing? Please keep an eye on them. Water changes for the nitrates are good, and sounds like you have aeration. What are your numbers for the ammonia and nitrites? What size pump do you have and how much water is it moving? Also, watch that you're not over feeding.

 

[Craig Brown]

A month or so ago, I was desperate and used an algaecide.

 

[Meyer Jordan]

What are the numeric values for the Ammonia and Nitrite?

 

[Craig Brown]

No, I have a pretty big easypro skimmer with a pump rated for much more water. The skimmer is also fed by the bottom drain. The waterfall is rated for a bigger pond. It has three of those colored mesh filters and two bags of bio tape. I also keep 10 lbs of activated charcoal in it. I should have provided a better description. I built the structure. It is above ground and below ground. The second and third pond are above the big pond. As stated, aside from high nitrates, the chemistry is near perfect. The water is also very clear (it wasn't when this photo was taken)

I tried an experiment and added another air stone. They do seem more perky. If you look at the photo, you can see that it also has two other small waterfalls. I figured between those and an airstone it was plenty. But maybe because it is a defined rectangle (it has less surface area in contact with air) it needs extra air. My pump can support several more stones. If that is the only issue, no big deal.

 

[Craig Brown]

Don't know the exact numeric value of the Ammonia and Nitrite as the kit shows colors that you match with the test tubes. But definitely the first color (close to zero).

 

[Tula]

Glad they're more perky, with i increased O2. The bigger they grow, the more O2 they need.

 

[Mmathis]

I like the way your pond is set up.