flood.

[williampaul]

ok this might be a stupid question but how do you keep your house from flooding when the power goes out to your sump??
my power went out and i lost about 10 gallons in my apt, is there a remody?

[jlemieux123]

You can first of all make sure that your return pipe is ether close to the surface of your tank or have a hole close to the top to break the sephion. Or you can buy an anti back blow valves and install them in water return.

[jdieck]

While the pump is running the water level in the tank goes a bit higher than the overflow. As the pump starts that water level of the overflow lowers only to the level of the overflow unless your return pipe is under water and syphons the water to a level below the overflow. To prevent the syphon drill a small hole at a level right under the water surface in the main tank when the pump is running. Once the pump stops and the water levels drops air will enter the return pipe trough that little hole and break the syphon.
Alternatively you can use a check valve in the return line although eventually they leak and if the outage is long the water will still back flow.
The picture below will help to better understand how this works.

[coast2coast7390]

use a check valve somewhere along the return line
but the over flow should take care of its self

[tmz]

Once you have accompished drilling the siphon break hole,you should calculate how much water will empty into your sump from the pipes skimmer, tank etc. and ensure that you keep the water level in your sump low enough to accomodate it. Many draw a line in the sump to establish a m aximum fill level for top off which will accomodate drain out during an outage. If your sump is too small to handle it you can create an overflow bulkhead in your sump leading to another container for drain out overflow.

[mouscacha]

I heard check valves tend to back up from gunk build up.

[rogergolf66]

How large is your sump and how large is you display tank?

[Kryptikhan]

Originally posted by jdieck
While the pump is running the water level in the tank goes a bit higher than the overflow. As the pump starts that water level of the overflow lowers only to the level of the overflow unless your return pipe is under water and syphons the water to a level below the overflow. To prevent the syphon drill a small hole at a level right under the water surface in the main tank when the pump is running. Once the pump stops and the water levels drops air will enter the return pipe trough that little hole and break the syphon.
Alternatively you can use a check valve in the return line although eventually they leak and if the outage is long the water will still back flow.
The picture below will help to better understand how this works.

this post is the exact reason i read this board like the morning newspaper...even though i dont read the morning newspaper. lol

learned a lot here

[williampaul]

its a 75g display and a 20 gal sump/fuge. this gave me a reason to go ahead and put deviders in my sump. thank you to everyone. i really appriciate the feedback on how to fix my problem. has anyone used a battery backup?

[gowlover]

Thanks Kryptikhan! Helped me a great deal also!

[jdieck]

Originally posted by williampaul
its a 75g display and a 20 gal sump/fuge. this gave me a reason to go ahead and put deviders in my sump. thank you to everyone. i really appriciate the feedback on how to fix my problem. has anyone used a battery backup?

Unfortunately battery back ups do not last long runing pumps, may help for running powerheads and an air pump but not much more. If you really want a backup you will need a generator.
In any case even with a backup I would not count on it to prevent a flood. I usually design the system to fail to the safest mode.

[Kryptikhan]

Originally posted by jdieck
Unfortunately battery back ups do not last long runing pumps, may help for running powerheads and an air pump but not much more. If you really want a backup you will need a generator.
In any case even with a backup I would not count on it to prevent a flood. I usually design the system to fail to the safest mode.

ok..so if i make the hole in the drain piping as stated above. I will be using a 20 long sump. Not gonna use a check valve. This will be in my new 72 bow. Is that sump large enuff to prevent flooding if the power goes out.....or am i missing info ?

[jdieck]

Originally posted by Kryptikhan
ok..so if i make the hole in the drain piping as stated above. I will be using a 20 long sump. Not gonna use a check valve. This will be in my new 72 bow. Is that sump large enuff to prevent flooding if the power goes out.....or am i missing info ?

Assuming the hole is at about the level of the overflow, the amount of water that will drain when the pump goes off is only that above the overflow which depending on the size of the comb and the flow rate may be anywhere between 1/4" to 3/4", the water that will drain to the sump.
To calculate how much water that is multiply that height (say 3/4") times the aquarium lenght and width and divide it by 231 and that will be how many gallons will drain.

Example:
Assuming your tank is 48"x18"x20" you calculate:
Gals = (0.75" x 48 x 18)/231 = 2.8 gallons Say 3 gallons
In other words while the sump is running it shall have at least 3 gallons of space available avobe the running water level.