August 11, 2015

Filtration Systems / Those Pesky Predators

Today's Pond Q&A

In this issue:

- Filtration Systems

- Those Pesky Predators


Question #1>

Hi Carolyn,

I saw your duck question recently. I have a 15 x 15 pond with two
ducks. I also have two dogs and 15 chickens that drink out of the

Before I had the ducks, I had a pretty healthy bunch of lily pads.
I have had the ducks about a year. They pick through the lily
pads, but they do not tend to eat them.

I have a AquaMax pump and filter that does fine work with the
duck-debris (highly technical language), but the water is fairly

I am hesitant to do your 25% weekly water replacement because I
live is Southern California, and I feel guilty about the water
usage. Anyways, you may want to suggest a "mature" lily pad
solution for duck-lovers.

Would the Microbe-lift do anything for my pea-soup colored water,
or is my only solution the 25% weekly water replacement?



Answer #1>


Microbe-Lift will do a lot to remove the organic waste in the pond,
but a really strong filter with good mechanical filtration in
addition to the biological filter will be necessary. A friend of
mine with the turtle pond learned this lesson the hard way after
losing all his turtles to a bacterial infection. He now has a
state-of-the-art filtration system in place. It won't happen
again. The lily pads are not really "safe" from the ducks.
Eventually, or perhaps by a different species of duck, the lilies
will be devoured by them. I have always wanted to keep ducks, but
after seeing how much pollution they generate, I decided against
it. Koi are not much better, but I chose koi.

I understand the water rationing. Still, the solution to pollution
is dilution, so a bigger pond may be the answer if water changes
are not plausible.

Mechanical filtration would be a series of baffles, such as vortex
chambers, brushes and matala mats to trap progressively smaller
particles. This would clean the water of what we call inorganic
matter, the stuff that takes longer to break down, and leave the
actual chemical filtration and biological processing to the
bacteria. You can do a DIY with individual or partitioned
chambers, just as long as the water has to go THROUGH the filter
materials and not around it. By putting the pump at the end of the
mechanical stages you will be able to clean the water much better.
Clear water and clean water can be two different things. You may
already have very clean water but now let's work on the clear part.

If you aren't into a DIY filter, you can buy and install a retrofit
bottom drain, connect it to a vortex, going into a second vortex,
and perhaps follow that with a bubblebead filter. In the second
vortex, you can use the matala matting to catch particulate matter.

The trapped debris can be purged or washed out of the mats without
losing very much water. But if you do not get that debris out of
the pond system, you will not have any success in cleaning up the
pond. The water will naturally decline unless there is a way to
remove the pollutants at a rate equal to the rate it is building in
the pond.


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Question #2>

Hi Carolyn,

I built my first pond this past spring and have become completely
addicted. It is approximately 1200 gallons. I have 3 gold fish and
3 koi (approx. 6"). Up until the past few days everything has been

My problem is 3 days ago one of the comet goldfish disappeared
overnight. I assumed a predator, because I have found no sign of
it. Now today I found one of my koi near death after seeming fine
this morning when I fed them.

I took it out and gave it a salt bath and have it in an isolation
tank. I see no obvious parasites although there are some scales
around the head than look "loose" and a little flaky. I treated
the pond with salt also.

What else should I do? It has been unusually hot here. Could that
be a problem? I am so attached to these silly fish, that I hate the
thought of losing them. any advice would be great.


Answer #2>


It sounds more like a predator to me. If the pond isn't built with
steep sides that make it difficult for predators to catch fish,
then the obvious happens. Cats like to fish but rarely try to eat
what they catch. And these fish are friendly...

A low fence might thwart a fishing cat. Friends of mine swear by a
black netting that is strung around their pond, on small poles,
that is meant to deter raccoons and other small fishing pests. So
far it has worked.

Or, better yet, use that AND one of the motion sensor scarecrows sold
sold by MacArthur Water Gardens and I doubt you will lose any more fish.


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

Brett Fogle
MacArthur Water Gardens

MacArthur Water Gardens
PO Box 3628
Alpharetta, GA 30023-3628

Posted by bfogle at August 11, 2015 12:30 AM