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Joyce Clark Unfiltered

For "the rest of the story"

In July my family and I vacationed in California. While we were there we visited two Koi farms. Lessons learned from those visits were that we needed to beef up our filter system and we needed to add shade.  Our adult children committed to working on additional filtration. My husband and I would work on the new shade component.

Our Arizona summers with temperatures over 100 are prolific breeding grounds for algae. When the temperatures rise above 100 you can see the algae practically multiplying before your eyes. In dismay the water turns dark green and murky. We know we have fish. We just can’t see them anymore. We knew we were on the right track with our small external filter.

12. filter system running

Four barrel external filter system

It just wasn’t large enough to handle the job. The small external filter was a waste receptacle with holes drilled on the bottom of one side. It was filled with polyester batting and a small pump and hose pushed water into the receptacle. The water filtered down and exited through the holes at the bottom side of the receptacle. It works and would work well in a small pond of perhaps no more than 500 gallons. But our pond is large. It is 15’ X 25” with a depth of 2’ to 4’. It is 7,000 gallons and the little external filter was like the little engine that could. It could do the job but didn’t have enough horse power to do the job well.

8. Water to bottom

Each barrel has different media
with a layer of A/C filter pad on top

The first thing the kids did was to yep…surf the internet. They got a lot of great ideas from You Tube. Many other ponders have apparently faced the same problem and shared their ideas.  They decided on a four 55 gallon barrel system. A heavy duty submersible pump would deliver water from the bottom of the pond. It would go to the bottom of the first barrel filled with lava rock which would filter out large clumps of algae and other junk. The water would then move to the bottom of the second barrel filled with ordinary kitchen sponges. The water moves to the third barrel filled with A/C filter mats and lastly to the fourth barrel filled with polyester batting. In each barrel the water is forced to the bottom and must move up to the top of the barrel so that it can move to the next barrel in line. From the last barrel an outtake hose takes the filtered water to our little creek and into the pond proper.

10. Intake hose and pump

Intake hose and pump
at bottom of pond

11. Outtake hose

Outtake hose dumps
water into the creek






©Joyce Clark, 2013


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Another Rube Goldberg pond contraption

Posted by Joyce Clark on May 28, 2013
Posted in fish pondKoi pond  | Tagged With: , , , , , | 2 Comments

Pond vac 1

Pond Vac

Having put together our shop vac system to muck the bottom of the pond I wanted something to combat the free floating algae in the pond water. Back to Internet surfing again. This time I found a suggestion for an external filter. Our filters are doing a good job but there is so much fine, lacy algae they simply cannot keep up with it all.

I went to Wal-Mart and bought another bag of polyfill batting, a round sprinkler and a tall kitchen garbage receptacle. Again, my purchases were under $20. The only other items needed were a piece of hose and a submersible pump. Fortunately we had both lying around.

The old pump is submersible and moves 600 gallons of water an hour and can completely recirculate the pond water in about 12 hours. We placed the pump is in a sack we made of old, screen door netting to protect it from becoming clogged by algae. We attached an old shovel handle to it so that we can pick up the pump and move it around without having to get into the pond.

External filter inside

Inside of external filter
Poly fill batting
Sprinkler and hose

External filter trash container

External filter
trash container
holes drilled in
bottom, front

External filter hose and pump

External filter
hose from submersible pump
to sprinkler in trash container







A piece of hose runs from the pump into the plastic garbage can filled with polyfill batting. Again we drilled about 9 large holes at the bottom of the garbage can on one side only and drilled a hole at the top on the side to slip the hose into. We attached the sprinkler to the hose end draining into the garbage can. We run this external filter system during the day from about 7am to 11pm. It has been working for about a week and we can see that the water is clearing.


Fish in May 2013

We will never rid ourselves of all the algae nor would we want to. The fish do eat the algae and as they root around the bottom and sides of the pond eating algae they disturb it and the fine stuff floats up to the surface. We do see clumps of this fine stuff on the water’s surface. I have tried skimming with our trusty pool net it but it is so fine, it just dissolves. However, it does float over to the internal filters where it is sucked into the system.

water quality 1

Water quality in May
in Arizona

As we enter the really hot part of the year in Arizona the water is becoming more cloudy and with time, we will not be able to see the fish. The filters will not be able to keep up with Mother Nature’s algae production.  I am determined, no matter the temptation, not to use chemicals this summer for summer will end, the water will clear and we will be surprised at how big the fish became while invisible to us.


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