[Birdman]

I wanted to build a cheap easy filter to take out fines on my 600 gal QT tank. I tried matting but diddn't like that. Tried sand but it fluidized, so I went with oyster shell. All in all it has worked exceptionaly well, keeping my water gin clear, maintaining GH and KH at 107, and easy to clean.

I started with one of my free fiberglass well tanks, the smallest size, just a little bigger than a 5 gal bucket. I just ran the flow from my pump into the bottom and put a 2" 90 out the top for the water to flow out to the tank. The top I cut out of the figesglass tank I drilled a bunch of fine holes in and layed it in the bottom of the tank for a diffuser plate.

Then I put a 2nd 2" outlet in it a few inches below the return to the tank to use for flushing. Fitted it with a removable stand pipe I can pull for flushing. I then filled it with 40 lbs of rinsed oyster shell chicken grit. It's been up and running for a couple of weeks now and I am very pleased with the results. It's keeping my water gin clear, and brought the KH and GH up to 107 ppm where it has stablized.