airhole in return output

[Craig]

I'm finalizing plans to finally add a sump to my setup. On the return line I'm going to have a scwd split to 2 u-tubes. I'm paranoid of flooding during a blackout and so someone reccomended that I drill a hole near the output. Has anyone done this on return u-tubes and if so where did you drill the hole? got any pics?

 

[DevIouS]

1/8" hole on both the returns, just below the water line.

 

[simike]

make sure you drill a holw in both sides, one may be blocked as he scwd switches outlets. make the hole like a half inch below water line or more depending how much your sump can handle

 

[House of Laughter]

What Mike said - holes aren't even necessary if your sump can handle the backflow volume.

House

 

[Alfredo De La Fe]

What I did was put a nipple in the PVC pipe going across the top of my tank to the returns. From the nipple I ran a small piece of airline tubing down to the waters surface. What this does is:

1. Allows the siphon to break when it reaches a certain point.
2. Allows you to clean the airline tubing during maintenance. (A drilled hole can get clogged and can be more difficult to clean of coraline algae.)

-Alfred

 

[fritz]

I use two holes incase a snail covers one then I decided to have my returns just under the water's surface. This way as the return shuts off the water will lower to below the return outlets and thus break the cyphon.

 

[tomzpc]

I prefer to have a sump that can handle the backflow siphoning like House mentioned but if you can't then the holes are a necessity.