Need help making a sump.

[Trustyworm]

Hi, I'm trying to make sump out of a 20 gallon tank without drilling my main 75 gallon tank. I plan on buying an overflow box, but I don't know which gph or gallons I would need. Also, what type of return pump will I need? I would also need to know the tubing for both the overflow and return pump as well.

 

[ScottJ]

The best siphon boxes, IMHO. https://www.lifereef.com/

 

[twentyleagues]

Hi, I'm trying to make sump out of a 20 gallon tank without drilling my main 75 gallon tank. I plan on buying an overflow box, but I don't know which gph or gallons I would need. Also, what type of return pump will I need? I would also need to know the tubing for both the overflow and return pump as well.

So without drilling the tank you are stuck using a hang on back overflow box. I personally have not had great luck with hob overflows. Maybe someone will be able to chime in on one that is fairly reliable. IMO they will all eventually fail to operate properly and cause a flood. But the overflow box will dictate answers to all your other questions. It will indicate what size drain tubes and how much flow it can handle. Choose your overflow and go from there.