breaking siphon on drilled returns.

[eric b 125]

i want to drill holes in my tank for the returns, one in each corner. what can i do to prevent/stop a siphon from starting should my return pump quit? i've heard of check valves, i think that's what i was told about, but learned that they werent very reliable. thanks.
Eric B

 

[naclh2o nut]

1
Could you not just drill at or above you water line? Once water dropped it would suck air and stop siphon. Just my thought.

 

[bmkj02]

Originally Posted by NaClH2O Nut
http:///forum/post/2966116
1
Could you not just drill at or above you water line? Once water dropped it would suck air and stop siphon. Just my thought.
You can do that or a check valve. I used a check valve on mine. Which check valves are better I have no clue. Spring type or flap???? MIne is spring type.

 

[eric b 125]

thanks for getting back to me, i thought no one really cared about this question. i didnt really know there were different kinds of check valves. do they cut down on your flow?
NaCl: the returns are going to be drilled 1.5" under the water line, and since the bulkheads are 1.5", the tank would drain 3" of water and flood the floor. where are you suggesting i drill these holes? i see how it works for over-the-top returns, but not drilled?

 

[valgae]

how much water is in your sump? when i cut off power to my tank the tank drains about 3" and it fits in my 30g sump.

 

[eric b 125]

i'm in the planning stage of this now, so i dont have a sump yet. i'm just trying to figure out how to avoid issues when i build it. i have to wait until the weather gets nicer around pgh so that i can paint it while its down. i have some drawings put together with all the measurements. i'll do some math tonight and get back to you on that, but i'd still like as many fail-safes in the final product as possible, so if there is any other suggestions, i'd sure appreciate them. i was going to build the sump with the idea of extra room in it for overflow, should the pump and valve fail. any idears?

 

[valgae]

on my tank the drains are 3" from the top. i just realized that i think you were planning on using an overflow so this really wont be an issue for you. but.... 36x18x3"=1944/241=8g of overflow water my sump needs to be able to hold if i should lose power. i have a 30g sump so... 30x12x6"=2160/241=9g my sump is 18" high so my highest baffle can only be 12". the remaining top 6" is for the 8g that can drain down during an outage. did i lose u? i think i lost myself.lol.

 

[eric b 125]

i'm with you all the way... im going to crunch some numbers and i'll let you know what i come up with to get your opinion. while i'm book-wormin it, i dont suppose you know what to sound-proof the cabinet with? i've used dynamat in my car, but i think it will take up a good amt of space. thanks a lot...

 

[naclh2o nut]

8
Sorry , my return is over tank. However, could you not put an inverted U in tank then drill a hole higher up, once it sucks air it will stop draining.
_[-]_ this is best I can do on keyboard. Imagine middle line at top. then you could drill hole at top of downward bend. Water level would stop there.

 

[eric b 125]

i hear what your saying nacl, but that would add so much head-pressure onto the pump, and if i was going to do that, then i'd just go over the top. i did the math, and with the 40 gal sump i'll be using, i will have the extra room in it when it's filled to allow the water drain 3" below the rim of the DT. I guess that's what i'll be doing to prevent flooding.

 

[naclh2o nut]

10
That is the easiest way.