check valves

[ddgluck]

Anyone have luck using the check values from depot/Lowes. I did a power failure simulation, and my supply feeds want to syphon more water than the sump can hold. So I figured a few check values would do the trick. Anyway let me know if there are good/bad, or if there are others you recommend it would be greatly appreciated.

Thanks
-dg

 

[DarG]

The only check valves I have seen at HD or Lowes are the Spring loaded check valves. These are not salt water safe as far as I understand. They either dont use a ss spring or the ss is not the proper grade for saltwater use. You need to use a flapper style check valve. You can usually find them at the online aquarium / aquaculture vendors. These have a rubber hinge that closes the stopper instead of the metal spring.

Have you tried drilling a small hole in the returns just below the normal water line. If your returns hang over the tank lip, you can do this. If they enter through bulkheads below the water surface, you cant. The hole will break the siphon on the return lines when power is shut down to the pump. It does allow some water to back siphon before it completely breaks the siphon but it's not much. But you still have to test it to make sure it stops before overfilling your sump.

 

[BLockamon]

As DarG said, a siphon break is your best bet. Even if you get saltwater safe check valves, they can leak. If you do use checks, use two back-to-back for safety.