I use to use two hanging fish filter on it. But there is just too much waste in the tank. The fish filters can't handle the waste that goes inside. Unless you want to clean it out every two or three days. I did think about building an external shelf. But that would be a lot of work for a filter system setup. I just wanted everyone opinion before I work on it. Hoping someone might have a better idea. Thanks.
TO be honest man, the only difference between your "pond filter" and a sump is the positioning of the Pump. You have the pump inside the tank and gravity feeds the returns.
A sump (underneith the tank, or Off to the side somewhere) would have the pump powering the returns, pumping water back into the tank and the tanks overflow would be gravity fed... So it's just a matter of where you want the pump. I would rather have it out of site and in the sump. You could put your heater in there as well. You already have a Sump. May as well set it up right!
You would only need to purchase a "Hang on Back overflow Box" to accomplish this. No Need to drill the tank at all! Easy to setup also...
Here is one example.
I would do a serch for the best price and maybe ask around for the best way to set it up.
Problem Solved!
I understand all that. I do have a sump setup that i am not using. I just don't like the watt of the pump that it outputs. Plus I don't like the noisy toliet water sound. And Also if my rbp get spook it will bump into the overflow box or electric goes out. There might be a chance it can stop the overflow box from working. I know that they have an air piece hook up to air pump to make the overflow work again. It just going to cost more money in the long run. I am trying to cut back on my bills. The pond pump I am using is only 30 watts. I do have 7 fish tanks and a pond running at the moment.
Well the toilet sound has been long ago solved with a simple "gate value" (not to be confused with a ball valve) under the tank below the drain pipe... You turn the handle until you hit eqaul librium in waterflow into and out of the tank VIA the Drain pipe. All of the gurgling noise goes away....
Why wouldn't the pump that you have now, work with the rubbermade bin (pond pump and filter) under the tank if you placed the pump in the filter box under the tank? Does it not have enough head power?
P.S. What's on the other side of the wall that the tank is on? Is there any chance of putting the Filter box in that room on a wall shelf and running the drains and return through the wall? it would only take a couple of holes and and maybe some 2x4's screwed to the other side of that wall for a shelf?