Based on the idea of "bigger is better", Im in the process of designing and building a new filter for my turtle tank. Its a rather simple design. It works like this, water is siphoned from the 120 gal to a 20 gal that is level with it. then the water is siphoned over the back of the 20 gal to an external overflow system. Water flows down into a series of rubbermaid containers which contain filter media and have holes in the bottom of them. The water passes thru 3 or 4 trays and ends up in a large container at the bottom which has a submersible pump (possibly with a float switch) which returns the water to the 120 gallon. All I can say is I sure hope it works, lol. Im about at the point where im realizing that im not doing this to save money, Im doing it because i like to build stuff. But I like the idea because the media trays will be like drawers in a cabinet and easily accessible. This whole idea is still under construction and may evolve as I go.
Below is the first photo of the recently built cabinet. I still have a lot of polying and staining to do. I will also be adding cabinet doors to cover the front. The section on the left is just extra storage and will have shelves. The upper media tray is not attached, its just holding on by friction.
-----
