Darren’s Kio Pond Story

I’ve been fortunate to have a relatively large (about 4900 gallons) koi pond at my home. The pond is 17 years old and most of my fish are over 15 years old. They have become pets. The filter system I used in the past was a standard set up of two 55-gallon barrels together in a simple do-it-yourself system. The set up had filtration pads in one barrel for solids capture and lava rock to hold the biological bacteria component in the other barrel. That filter system worked marginally in the past along with many great difficulties and problems.

“With DIY, cleaning was an issue.”

One difficulty has always been cleaning the barrels on a regular basis depending on how much sludge was captured in the setup. The filter pads had to be removed from the barrels, washed, and replaced, and then the lava rock in the other barrel had to be removed and washed. The barrels had to be turned on their sides and cleaned of sludge with high pressure water. Altogether, each cleaning was a dirty, time consuming mess requiring about two hours work. To keep relatively clear water I had to clean the barrels every few weeks. I also had to watch that the old system didn’t plug up due to lack of maintenance. It would often overflow and drain the pond of 3 to 4 feet of water, all in all a major pain.

“The pond water would remain so dirty that you could barely see the fish.”

I also have a great deal of plants in my pond including pond lilies that cover most of the surface area of the pond. The pond is beautiful, but this creates an additional problem. The pond water is often dirty with foreign material making the water brownish, plus the plants add a considerable amount of sludge at the bottom of the pond. If I didn’t clean the barrel filters every few days, the pond water would remain so dirty that you could barely see the fish. The filter system that I had built DIY was never very effective at cleaning the water. No matter how often I cleaned the filter barrels, the pond water became dirty again in a few days. It is amazing that my koi lived and even bred in that water.

“I had been searching for a cost-effective automatic filter system to clean the water for quite a few years.”

I was looking for a system that didn’t cost a small fortune and would automate the cleaning of the water. Because my pond had so much crud in the water, whatever I considered installing would require me to continually monitor the backwashing of the filter media. I didn’t want to get caught up in continually having to manually keep the water clean. To me that wasn’t much more effective than the old barrel cleaning system I had. The requirement of manually backflushing the filter system or continually replacing filters kept me from purchasing one of those other systems.

“That was the kicker for me, automatic backwashing!”

While researching pond filter systems last year, I came upon the AST Endurance filter. AST was known for building professional water filter systems for everything from zoos to corporate fish farms, obviously they knew what they were doing. The Endurance filter system was new and automatic. That was the kicker for me, automatic backwashing! It seemed to be designed for the little guy, like myself, and it was priced to be competitive with everything I had looked at in the past for my pond. I thought about the system for a few days and called AST. I ended up speaking with Michael Malone. He explained the Endurance system and it sounded like it would work for me. Michael gave me no sales pitch, he just gave facts: what the unit could do and what it was designed for.

“I ordered the AST Endurance 4000 unit in January 2017.”

The Endurance filter system arrived enclosed in a heavy duty cardboard box and strapped to a pallet. It was easy to move around and, with a friend’s help, we moved it to its final location. This unit is very well built with excellent fittings. The 4000’s operation and backflush frequency is controlled by an air pump and Dwyer air valve that comes with the unit. When the air pressure in the 4000 filter pushes the water level down to a certain level, it triggers an air release through a see-through pipe causing air bubbles to discharge through the bead filter media in the main chamber. This cycle causes the bead media to be washed automatically. The crud material collected on the beads in the main chamber falls to the bottom of the chamber and are swept into the sludge chamber by water flow. You simply vary the air flow by a readable Dwyer valve into the middle chamber to control the frequency of the auto backwash.

My pond had so much crud and particulate matter in the water, but gradually the water cleared up and so far that I haven’t cleaned the pump or input screen in seven months. The Endurance 4000 is working its magic!

“I am looking forward to only cleaning the input screen and pump input basket once every year.”

Now the sludge I find is down to what is remaining in the sludge tank of the Endeavor 4000. This system really works efficiently and automatically. I can see my fish clearly at four feet deep now! You don’t have to touch it except for draining the sludge collected in the sludge tank, and I think I will be filling up my bucket with sludge every two weeks from now on – the water is that clear and getting clearer every day!

An interesting point to remember is that sludge from the pond can make your garden vegetables and plantings around the home grow wonderfully. Our tomatoes were dynamite this year.

“What’s not to like!”


Darren Stevenson
AST Customer