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TRIX
12-06-2006, 04:09 PM
Hey. I would like to keep my return line below the water line. Is there any backflow preventors that I can use on the return line. My return line comes in at the middle of the tank on the bottom. I was hopping to do a spray bar along the bottom. But because this line won't go to the top of the tank if I loose power all the water would be sucked out of the tank and cause a major flood. Any suggestions. Thnx

muck
12-06-2006, 04:16 PM
I wouldn't recommend doing it that way but if you insist on it make sure you install a check valve on that line. (Try to find a True Union one so you can take it out to clean periodically.) Of course you would also need a ball valve above the check valve so you can close the line off when you take the check valve out to clean.

hawk
12-06-2006, 04:29 PM
You could drill hole(s) just below the waterline. This should stop the syphon when the water drops to the level of the holes. Keep the holes clean.

TRIX
12-06-2006, 04:58 PM
You could drill hole(s) just below the waterline. This should stop the syphon when the water drops to the level of the holes. Keep the holes clean.

The entire baffel would be at the very bottom of the tank.

TRIX
12-06-2006, 05:00 PM
I wouldn't recommend doing it that way but if you insist on it make sure you install a check valve on that line. (Try to find a True Union one so you can take it out to clean periodically.) Of course you would also need a ball valve above the check valve so you can close the line off when you take the check valve out to clean.

That's what I figured. A long term pain in the butt. Do you have any other suggestion.Should I scrap the baffel idea and just have my returns at the surface.

danny zubot
12-06-2006, 07:12 PM
If you "T" the intake pipe going into the tank wall, and run a pipe straight up the outside back of the tank so that it is above the water line, it should break the siphon when the pump is off. You need to make sure there is no back pressure from your spray bar or this pipe will be overwhelmed, and flood.

muck
12-06-2006, 07:25 PM
Better re-think that advice Danny. :lol:

Sure its no longer a syphon but the water is still going to backflow into his sump.

muck
12-06-2006, 07:28 PM
I would run the return over the back of the tank or up through your overflow box and have the return near the top.

If you want to run the baffle system still put it on a closed loop. No worries about backflow and syphoning then. Only downside is you need another pump.

danny zubot
12-06-2006, 07:34 PM
After reading the post again, I realized that missed this part.:surprise:

My return line comes in at the middle of the tank on the bottom.

In that case, please don't take my advise.:smile:

TRIX
12-06-2006, 07:34 PM
If you "T" the intake pipe going into the tank wall, and run a pipe straight up the outside back of the tank so that it is above the water line, it should break the siphon when the pump is off. You need to make sure there is no back pressure from your spray bar or this pipe will be overwhelmed, and flood.

The return goes into the tank dead center on the bottom for 4 sides of viewing. Would this still work

MikeP
12-06-2006, 09:25 PM
My 190g has the same thing. Originally I thought of doing what you are thinking of. For fear of flooding I had another return drilled (through the back on the opposite side of the overflow). That bulkhead is still below the water line but in addition to a check valve I designed my sump to be big enough to handle the additional water if I did lose power. What I plan to do to do with the bulkhead in the bottom of the tank is run some PVC strait up and just above the overflow so that if my overflow ever got clogged it would act as a back up overflow.

HTH