When I decided to design a pond for my backyard, I was under the belief that the most inexpensive way to create a filtration system for my aquatic paradise would be to Do It Yourself or DIY. I went about researching / purloining the design of filters and gadgets that would be put into practice on my pond. I made numerous trips to the local box store (sometimes even returning within an hour) and searched Craig's List to collect the materials. I cut a lot of pipe and applied much primer and glue to PVC. After little fanfare, a filter system stood in place.
Now my filter system consist of: five 55-gallon barrels, each with a two inch input/ ball valve. The water in the system enters each barrel and is turned 90 degrees by an elbow. Then it travels through a rough-grade circular floor scrubber pad, 9,000 feet of binding strip, and flows out to the pond's water-wall by two 2-inch outflows. To clean these barrels, I provided a two-inch outflow, with ball valve, on the bottom. There is no waste line anywhere nearby, but I have a good procedure for dealing with the cleaning of the filters that uses a submersible pump, a five-gallon bucket, and 50 feet of collapsible hose. I have a hose line, with a ball valve, tapped into the mainline to wash the filters with pond water. The waste water from the filters ends up flowing out to the municipal sewage system via my garage utility sink. The system worked; the water flowed in, the water flowed out. Mission accomplished until my first cleaning.
That day came a "few" weeks later. I figured I'd let the system build up some good bacteria before I came along and stripped some of it away. I set up my cleaning line up and started draining the first barrel. The water fell into my catch bucket with a little debris, but relatively clear. I smiled and thought good clean fun. That smile remained until the barrel emptied and I applied the first 5-gallon bucket flush of pond water. The watery contents (and I use that term lightly) that gushed from the outflow pipe were not only the direct opposite of the earlier contributions, but smelled of sanitation gone wild. Now I've been to places in this world; and I thought I had been party to foulest of foul. I was wrong; olfactorily wrong.
The stuff that oozed forth was darker than a moon-less night. Its pungent aroma seriously made me cry. One accidental intake of this gaseous air and my head proceeded to spin out of control. This was not meant to be experienced, it was meant to be flushed; and better sooner than later. I proceeded to empty 10-15 buckets into the filter media before I saw great improvement in both clarity and stench of the filter water. Soon after the cleaning; I took a shower. I hadn't really splash any of the watery mess on to myself. It just felt right to wash from head to toe. At that moment, I knew, I had experienced something that should not be repeated.
Since my first encounter with the filters I have gotten excellent advice (suggestions) from my club's KHA on cleaning of the filters and learned the subtle indicators that signal a filter cleaning. My filters are in much better shape than those first few weeks; and my nose thanks me.