Siphon Breaks

[brians_224]

Thanks for your time.

How big should the holes for siphon breaks be?
Do they need to be below the water surface? In the over flow, should they be below the durso standpipe h2o level (2 inches below the rest of the tank) so they are always submerged or can they be above, so that you minimize the amount of h20 that is back siphoned to the sump in the event of power or pump failure.

I'm installing my return and need to know how big and where to drill the holes

Thanks for your help!

[Glass World]

You shouldn't need syphon breaks in your overflow at all... a properly functioning overflow shouldn't stop... well... overflowing shortly after your return pump stops. If it doesn't, then you have another problem.

As far as the syphon break on the return line goes, it can really go above or below the waterline, but I think most people put them below the waterline to make it quieter and minimize splashing. The disadvantage to putting it below the waterline is that in a power failure the water line will need to drain enough that the syphon break can get air into it... this means that if your syphon break is below the waterline then more water will drain into your sump in case of a power failure. Not really a big problem unless you're really lacking space in the sump.

Size really depends on the size of the return line. I'd start with maybe two 3/16 inch holes, then shut off the power and see if it works... if not, add another hole or two or increase the size to 1/4 inch. It's not a bad idea to have a few more holes than you really need to be sure that it will work even if a snail or some algae is blocking one of the holes.

HTH

[brians_224]

Thanks for your input.

I'm using a 3/4" return line.

[Glass World]

Originally posted by Glass World
You shouldn't need syphon breaks in your overflow at all... a properly functioning overflow shouldn't stop... well... overflowing shortly after your return pump stops. If it doesn't, then you have another problem.

I guess this is what I get for not proofreading my message... the above should read:

A properly functioning overflow *should* stop... well... overflowing shortly after your return pump stops.

[brians_224]

I understood your intent.

Thanks