Overflow leaks

My overflow is leaking. When I turn off my pump I noticed that the water from the main tanks leaks into the overflow area. No real big deal except if power goes out and I am not home. It would take about 4-6 hours till the leak allows enough water into the sump and it overflows.

Any way a fixing this without draining the entire tank? I have tried using a reef safe putty but because the water is leaking in it does not hold. I can slow it down but not stop it. Any ideas would be a big help.

Thanks in advance.

Tony

 

The leaking shouldn't be an issue since the height of the standpipe is where the siphon will break and backflow stop. The overflow box level can equalize with the display but it will not drop any lower than the standpipe. You should have that much room in your sump anyway since most skimmers need only so much water height to work best.

My 100G display back flows 3.5 gallons to my 30G sump worst case and that is easily contained since the sump level is always about 2/3 full so 10+/- gallons of freeboard at all times. 3.5 gallons in my 5 foot 100G display is 3/4" off the surface before the siphon breaks at the standpipe and return levels below the surface.

 

Just shut it down and remove the overflow box to make the repair.

 

Is it a corner overflow like a marineland or one that you drilled the tank and put the little overflow box in it that you can remove?

 

I'm guessing it is an internal overflow box. Again no big deal since it will only drain to the top of the standpipe before it breaks suction.

 

Yes it is a corner overflow (I had them made when I built the tank. The old ones that came with the used tank were nasty so I just replaced them) and the leak is about halfwaydown where it is sealed against the glass of the tank. The problem is when I turn the pumps off the water level inside the overflow is the same as the tank. Usually you turn it off and the water level inside the overflow is 4 or so inches bekow the display tank level. The leak keeps them level so approx 30-35 gallons will "leak" into the sump.

 

I wouldn't stress it much if it's a small leak. try putting some epoxy putty to patch it up. or drain the overflow and try to keep it drained and use some silicone to patch it up just make sure it dries up good before water hits it.

 

Your standpipe is too short if you leak that much back to your sump. That or your returns are too low in the tank and you are backsiphoning through them and thinking it is the overflow box.

Your standpipe should be just slightly lower than the bottom of the teeth on the overflow box so it cascades over but does not drop far enough to be noisy. Even if the box seams leak it will not go any lower than the standpipe. Assuming you have a standard 2'x2'x6' 180G tank and your level drops the normal 1" or so the most siphoning back to the sump would be 7.5 gallons of water which shouldn't be an issue if your sump is as large as it should be for the 180 display and at the proper operating level. You don't list your sump size in your signature.

How about some photos so we can all better help you without guessing?

 

I will post some pics this weekend. I am on the road with work and will not get home until Friday. Sump is 60 gallons.

 

I am guessing a simple DIY Stockman or Durso standpipe is your solution and a quick inexpensive fix.