is it a good idea to use a check valve on the return line?

[rdefino]

Should a check valve be installed on the return line? If the pump shut off, would it drain the tank into the sump?

Also, someone mentioned drilling a hole in the return line just below the main tanks wither line, about 2" below.

Thanks

 

[VLDesign]

IMO: Check valves in general are not a good idea. They are fine until they fail and you don't have enough space for the water and it floods.

I never use them and always make my sump big enough to handle all the water in the lines as well.

 

[Bud8Fan]

I agree, check valves are not a good idea. Drill a small hole for a siphon break instead, it's fool proof as long as you make sure it stays clear (not clogged).

 

[Dr Joe]

The anti-syphon holes are .250" in diameter (smaller holes tend to clog and single holes are almost guaranteed to) and placed just below the lowest water level you will have in the Aquarium. Two should be placed 180* apart in both the overflow and return lines.

Dr Joe

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