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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