Comment

Comment by Jon Parr on January 26, 2012 at 6:22am

I too, could not see your system on the link provided, but it sounds like you pump from FT to GB, GB drains to sump, sump pumps to FT, right? If so, no amount of fancy pumps, switches, or timers will insure that one of the pumps will not fail at some point. Assume that a pump WILL fail, and design accordingly.

Try this: pump sump to GB, GB drains to FT, FT drains to sump. If it is not possible to drain GB to FT, then pump sump to GB and FT simultaneously (using one pump and a flow valve to the lower of the two, or two pumps, 1-FT 2-GB) and both GB and FT drain to sump. I believe this is called CHOP or CHOP2, should be diagrams around. A SLO will keep the FT full no matter what.

Comment by Peter Shaw on January 19, 2012 at 8:34am

(I could not see your system but the only way your tank can overflow is if the water is pulled off the bottom.)

I know most systems generally suggest putting a pipe down to the bottom of the fish tank and pull all the waste off the bottom. But doing so can cause a problem.

If your pump is filling the diameter of the pipe that drains the fish tank and your power goes off you will have created a siphon and the water will drain out.

Solution: Oversize the piping from the tank, so that only part of it is filled when the pump is running, Secondly, put a few holes on the top of the pipe or 90's where it exits the tank, this will allow air to enter and break the siphon.

peter