anti-siphon help

[gaubow]

Ok- I am adding a much bigger pump from my basement to my display tank which is in my living room directly above. I have redone the current outlets into my tank, staggering them at much different levels. My concern is that if I have a power outage, the return that i have within three inches of the sand will be so deep in the tank that it would suck my tank dry.

Do I put an anti-siphon hole on the outlet lines that come from the pump? Is there something that I can install on the line that will prevent water from flowing backwards, down into the sump?

Thanks for any input.

[BoomerD]

You DEFINITELY want anti-siphon holes in your return lines, EVEN with a quality anti-siphon valve in place...NEVER trust any type of anti-siphon valve to work right in an emergency. A bit of algae, debris, or even an errant snail can block the flapper, and allow a flood in a power outage.

[mkpaulson]

do You think a check valve would help out in your situation.
http://www.aquaticeco.com/index.cfm/.../8229/cid/2043

[gaubow]

My sump is protected from my overflow, so it would only empty the tank a couple of inches, which is no problem. so my return lines, I should go ahead and drill a 3/8 in hole just below the water lines right?

i also ordered the check valve as you suggested.

[coral keeper]

you need to something because if you have a power failure you are in trouble. Why would you have pne that low anyway?

[gaubow]

It's not the return to the sump, it is an outlet from the sump. It is put that low to help keep a current running behind the rocks...

[skimminalong]

In my return line I have a 1/8" hole and it works great. The only thing I need to do on occasion is make sure it isn't clogged.
IMO, a 3/8" hole seems too big since water will be coming out of it whenever the system is running. As long as the hole is not clogged the syphon break will happen during a power failure and the floors will be saved.
Or think of it this way...start small and you can always make the hole bigger but if you start with that 3/8"...

[Yarr]

id be inclined to use more than a single hoel in the returns. maybe not 3/8 as that is pretty big but a few 1/8 holes in each should add redundancy

[mps9506]

I've had miserable results using check valves in tanks. Partially my fault, the valves would get clogged open with debris from the plant tank. But no matter how much filter material we used pre pump all the check valves got clogged (all 4...).
Plus they do add a good amount of head to the line also.

[Yarr]

I do not see how check vcalves or any other mechanical device coiuld be 100% reliable in a tank system. There is too much room for error. It does not take a lot to clog them open. even partially this will still allow quite a low of flow through them and possible onto your floor.

[BoomerD]

Even with a check valve (anti-siphon valve) in the system, you NEED the anti-siphon hole(s) in the return for safety...

[ScottT1980]

The reason you need not only an anti-siphon hole, but one that you monitor regularly.

LOL...it never ends guys!

Take er easy
Scott T.

[BoomerD]

Ah geez, I remember that thread...Another reminder to clear any algae or other detritus from those anti-siphon holes. When I was battling hair algae in my 90, I had to clean the holes weekly. Also, a good reason to add more than one hole, is the possibliity of a snail camping over a single hole at the most inopportune time could cause a flood. Remember,
"Murphy was an optimist"...

[Witfull]

my fav addage,,,,hope for the best,,,,plan for the worst.