August 03, 2006

Koi Pond Filtration / Koi in Hiding

Today's Pond Q&A

In this issue:

- Koi Pond Filtration Problems

- Koi in Hiding


Question #1>

Hi Carolyn,

I have a large Koi Pond. About 1500 Gals. I have a UV Filter
installed and it has done nothing. The pond is filthy. What else can
you recommend?

I feed the Koi twice a week. I have no way to drain the pond. I
did have a company come out but was very dissatisfied with their
service. They drained somewhat of the pond but never cleaned the
gook from the bottom. I did buy three fish that supposed to clean
the bottom? Any help I can get please advise.

Does your company sell a submersible pump and if so how much doe it
cost? Also the cost of Microbe-lift. How often should I feed the


Answer #1>


Do you have a filter on the pond? Do you have a bottom drain? Do
you have a big enough filter? Koi are pretty dirty fish and need a
lot of filtration. If you are feeding them, try cutting back on
the food. You also should be doing 25% water changes every week.
If the pond is unacceptable now, or at anytime, you can do a 50%
water change today and another 50% tomorrow. Always use
dechlorinator if there is any chance of chlorine or toxic metals in
the incoming water supply.

I suggest you buy a submersible pump specifically to pump out the
water from the dirtiest part of the pond for water changes, or you
can get a wet-dry shop vac to vacuum out the dirt, and just refill
with fresh water using dechlorinator. You should be doing this at
a rate of 25% weekly. Otherwise, the system is going to crash.
Microbe-Lift makes bacteria that will help biodegrade the organic
waste in the pond, but you still ought to have better filtration.

Check the products and prices on or
go directly to these pages:
Feeding the koi: feed only as much as they will consume in 5
minutes. Scoop any uneaten food out after 5 minutes. They are
small and do not need as much as you think. In fact, it will take
4 days for the food they eat today to leave their bodies. Most
people feed their fish 1-3 times a day, small amounts. Less is
more in the feeding department. If the pond starts to cloud up,
you are overfeeding them. Do a water change and cut back on



Question #2>

Hi Carolyn,

I have about 5 koi fish in my pond and they were swimming about all
day from one side of my pond to another. The past week or so the
fish are hiding on one side of the pond by a rock and they're not
swimming around the pond. They are also barely eating.

What do you think is the problem with these fish?

If i move them with my hose they'll swim around that area and go
right back to that spot. Please inform me with your opinion.

Thank you.


Answer #2>


It sounds like they are being terrorized during the night. Perhaps
you have raccoons visiting the pond when you aren't looking.
Predators will scare fish badly and they will act much like this.

Do a water change and test the parameters to make sure it is not
something in the water first, but you might need to watch the pond
closely for a while.

If it is predators, something that helps is to float styrofoam on
the top for shelter. You can buy sheets of styrofoam at Home
Depot. I presume you have Home Depot in your area, no?


========== @SK Carolyn =================
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Happy Pondkeeping!

Brett Fogle
MacArthur Water Gardens
MacArthur Water Gardens
1698 SW 16th ST
Boca Raton, FL 33486

Posted by bfogle at August 3, 2006 09:49 PM

Question #1 needs a pool vac so that when doing recommended water cahnges he/she can vacuum the muck from the bottom.

Posted by: Richard Renshaw at August 4, 2006 09:43 PM