Deb Spencer from Water's Edge gave a very interesting and informative presentation on bio-filters at the March 19, 2014 meeting of TAWGS. Mechanical filters help protect the pumps in our ponds and collect and remove debris. But the main purpose is to get rid of the things we don't see, ammonia and other sediments to keep our fish healthy. You cannot have a filter that is too big.

The different parts of the filters were shown and discussed. There is the tank where the water enters the bottom and flows up through poly filter mats, media bags containing bio-balls or lava rocks, through the top screens, over the top, into your pond. The top screens can be camouflaged with plants which will also help filter the water.

Deb also demonstrated and discussed the different media materials used in filtration systems based on their ability to clean by specific surface area (or ssa) per cubic foot. The higher the ssa, the higher the filtration. Pea gravel has a 72 ssa, lava rock 86, bio balls 120, bio ribbon 160, poly-flow 290.

She also gave us information about gravel bog and pottery bog filtration. To have a successful filtration system it requires these things: right temperatures, oxygen, food source, surface area and carbon.