As anybody who has kept fish knows, water quality is the most important element affecting your fishes health. If your going to keep healthy fish, you have to learn to keep healthy water. Goldfish, have a tendency to pollute their environment faster than other fish, so the goldfish-keeper has to take more aggressive measures to keep the tank clean, and balanced.
Regular Under Gravel Filters work by drawing the debris into the gravel where it breaks down. These systems seem to work for a while, but as the system ages, a buildup of debris under the filter plate causes it's function to drop off. The Reverse Flow idea is, that if you pump clean filtered water under the filter plate, debris that settles on the gravel will stay at the surface, where it's easier to vacuum up, or become stirred up by the fish, so the filter can draw it in. The biological breakdown, and collection of debris will be in the external filter, where it's easier to clean. Thus, a cleaner environment for the fish, and an easier task for the fish-keeper to maintain that environment. Also, since the filters on this tank process 350 gallons per hour, the output even though it was run through a spray bar, created a lot of current that poor swimmers like Lionheads didn't seem to care for.
My quest to keep very healthy fish is what inspired me to build this Reverse Flow Under Gravel Filter system. I have read of several people who use such systems, but the lack of information, and readily available parts, has brought out the inventive side of me. Here are some photos of what I built.
Enjoy, but remember that all images are the property of TABco Industries.
Filter plates are easy to find. Adapters to convert them for Reverse Flow are not. I made mine from CPVC pipe and fittings (the stuff used for drinking water pipes). All pipes and fittings in these pictures are CPVC unless noted otherwise. The two plugs in the first picture, are 3/4" caps, which I machined the outside diameter on a lathe to .999" so they would press into the holes. The caps that came with the plate, did not fit too tight, and since the underside of my plate would be under slight pressure, instead of a slight vacuum, I opted to make tighter fitting plugs. The second photo shows two reducer bushings which are pressed into 3/4" caps and installed with the bushings facing up. Note that the cap on the left has been drilled out to allow the output of the system to go under the plate. The cap on the right is undrilled, and this fitting will only be used to help support the intake diffuser I made.
The first photo shows some of the sub assemblies that I glued up in advance. The second photo is a close-up of the intake diffuser. Made from 1/2" and 3/4" CPVC fittings and pipes. The head, is a piece of 3/4" pipe, with 32 holes 3/16" diameter. The short piece of 1/2" pipe in the underside of the tee will only be used for support, and will be in the right (plugged) hole in the filter plate.
The first photo shows the adapters for going over the top of the tank that were made from four 45 degree Ells, and two 90 degree Ells and four very short pieces of pipe. I liked this arrangement better than using all 90 degree Ells, and short pieces of pipe, since it gave a cleaner appearance to the project. The second photo shows the plastic supports that will stabilize the pipes under the stand. The adapters are 1/2" CPVC to 1/2" NPT (threaded fittings). Hose barbs will be threaded into the adapters to connect the filters with vinyl hoses.
View from behind the tank is very clean and neat. No filter boxes, or ugly flex lines. Just two vertical pipes going over the top, and tucking under the edge of the cabinet.
The first photo shows a close-up of the top edge of the tank, with the plumbing going over the top. The second photo shows the return line (left) and intake line (right) in the empty tank. The fittings were not glued into the filter plate for easy disassembly. Also note that I kept the wording on the pipes faced away from view.
You need to look from the side of the tank to get a good view of the plumbing. From the front, the view is obscured by the placement of a rock group and plastic plant. The fish are returned to the tank and move in to check out my work.
OK, so this Lionhead is more interested in the airline, then the new filter plumbing.
See my fish.
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Wet PageSee more fish including my Whale.
The
Fish PageSee how big some of these fish have grown to.
The Fat Fish PageSee my Betta Castle
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