Return from Sump - To drill or not to drill?

[Danroth]

Okay, so I'm going with a overflow box from Glass Holes, and I'm picking up, from what I can research, the 1500 gallon overflow box. They suggest two returns 1/2" thick for that box, which I'd planned on doing a return on each side of my tank (120 gal) anyways.

What I'd like to know is they did have return kits there, for drilling in. What are people's preferences? Is having them over the rim versus drilling more safe? I see some talk about siphons & overflowing during power outages, but as I'm no plumber and I've never done this before, I really don't have a clear understanding. I just want to make sure I do it once, and do it right.

Any suggestions, feedback, opinions, personal preferences, and/or stories would greatly help.

Thanks in advance, as always.

[Jim_Dont_Care]

i dont drill because its easier to maintnance pumps in my opinion at least for me it is and another reason i dont have room for a external pump either

[1CARPENTER]

I personally have mine over the rim! But it does syphon when the pump shuts off, only because I have no check valve on my system. Although my sump will handle all the extra water!! Anyways all you need to do either way is install a one-way check valve on the return line! Drilling always looks nicer but may not be worth the risk of an accident if looks aren't that big of an issue?

[reefone]

drilling realy is only going to improve the look as now you dont have the plumbing going over the back of the tank. either way you go you should still drill a hole just under the water line for a syphen break and not rely on a check valve.



when the tank loses power the water will drain from the dt to the bottom of your overflow box. if you have no syphen break in your return line the water will keep syphening until it reaches the bottom of the return line and it ***** air breaking the syphen. with a small hole drilled into the return line just under the water as the tank is backflowing when power is out once the water level drops under the hole it will allow the return line to suck air causing a syphen break.

heres a link on how it all works.
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