Here are a few shots of my main filter showing the dirt buildup. It acts as a mechanical and biological filter.
Rectangular black polyethelene upflow filter with lid. It is a liquid shipping tote.
Measurements: 44” long x 29” wide x 29” tall. Holds about 100 gallons. Bottom is narrower than top. Has 1 – 2” bottom inlet, 2 – 3” outlets, bottom grate and 3 – 2” thick horizontal layers of filter matting. I added a layer of window screening between the grate and the mats. Maximum recommended flow rate: 2400 GPH. I put about 1500-1800GPH through it.
on the opposite corners. A little clay tossed on top cleared after a few minutes from the back corners. I may try to improve this by moving the outlet openings closer to the center.
UPDATE: I have moved my airpump into the filter box to see if the extra aeration helps with nitrification in the spring months as I begin to feed. I will need to find a method to check overall water disolved oxygen in the pond once summer hits.
