Originally Posted by dwayne.aycock
I agree...just be sure to get an overflow valve in case your power goes off. Your tank would start to siphon and overflow your sump, leaving a river of water all over your floors.
Proper planning can easily avoid this. When I shut off my return (for reaching the bottom of my 110 gal
, 31" tall tank) the return reverse syphons back to the sump. Once the water level falls below the return nozzle, the syphon is broken and the backflow stops. This happens well below my overflow as well, so does represent the worst case scenario ( same as a power outage). As I have ample room in my sump for the DT to do this backflow, there is no disaster or rivers. And then I can reach the sand without getting my armpit into the water.
My sump normal level is only about 8" or so to the top of the return baffle. That determins my sump capacity for backflow.
Word of caution, if you decide to go with a checkvalve on the return line, they can leak. If they do, and you didn't provide enough room in your sump for a full backflow of DT water, then you could have a disaster as mentioned. So, checkvalves are a "fool's caution" and may not provide adaquate protection. Proper planning will.