How to deal with a black out?

[romak50]

Hi guys, would appreciate any sugestions to deal with the followng scenario:

I have a 6ft tank with a sump, and have had a couple of power shortages in recent weeks that have caused the pump to stop, which leads to about 40 pr so litres of water running back down the return, overflowing the sump, and resulting in an angry wife.

Does any one have any suggestions on how to avoid this? Was thinking of some sort of one way flap over he return, or a portable generator that can click in with a power outage?

Anyway any advice would be great.

Cheers

[littleV]

generator for sure

[fishdance]

You can get water check valves but these will only work on your return pipe since they passively allow water in a one way direction only. You can also get electrical solenoid switches to close your drain pipe but like your generator idea, I think they are too complex with a corresponding increased risk of failure. Solenoid switches are available at irrigation shops and they will quickly realise what your predicament is. Make sure to get one that CLOSES with NO power of course.

40 litres overflow is a lot. How high is the tank water level above your drain? It must be a side drain? Can you use an elbow to modify into a horizontal drain? How big is your sump? It sounds like the volume is too small. I would either replace your sump with a bigger/taller sized one or add some extra sump volume with another tank linked with pipe.

[Josh]

How full is your sump normally and how does your tank water get to your sump ir overflow box, weir standpipe?

josh

[romak50]

Thanks for the advice Little V, Josh, and Sundance, and will definitely look at those options.

To answer a couple of questions, if I lose power the water will run down the return until it drains to the bottom of the return, and that is 2 inches below the water level. Using a trusty volume calculator the water volume contained in 2ft x 6ft x 2inches of water seems to be 56 litres - more than 40 litres, but the sump takes a bit of the overflow before the floor takes the rest.

The wier is not the problem because there is only a 1cm difference between the top of the overflow and the tank waterlevel.

The problem might solved by increasing the size of the sump. Its a 2 x 1.8ftx 1.4ft high, which is about half full. Do you think maybe a bigger sump that would contain the overflow might be another solution?

[Reillin]

I think the best temporary option is for you to drain the water till it is level with the overflow. Then fill up the sump till it is almost full. This will solve your problem with the overflow, since water pumped from the sump to the tank will simply overflow back into the sump. So basically, your waterline will only be just above the return outlet. Although, I must warn you that if the pump has too high a flow and there is not enough water returning to the sump, then it may run dry and burn out.

For the long-term, you can always move the return outlet a little bit higher. This can be achieved by professionally drilling a new outlet, or use a siphon-overflow S pipe. The latter option is a little bulky, but it avoids the unnecessary danger of cracking a tank. Of course, a bigger sump can answer your problems and might be the least problematic, but it would also be the more expensive of the available options.

Cheers,

Vien.

[Josh]

As long as there is enough capacity to hold the extra 56 liters then there is no need to get a bigger sump.

Work out the capacity of you sump and then take off say 65 liters, to be sure it doesnt overflow. You should be then able to make your sump to a level that is needs to be filled to when the pump is running

[BaZ]

I always go through the same process as Reillin when doing water changes or adjusting water levels.

I let the tank drain until it stops of its own accord, then fill the sump right up.

If the power goes off I know I can't have too much water for the sump

Of course this depends on the type of sump you have as to whether it will work when full like that...

A generator won't help you unless you want to leave someone on guard 24hrs a day waiting for a blackout.

[david11]

A smaller pump or slower flow should also work although you water level will not be as high. This wont fill your tank to 2 inches over the return but 1 to 1.5 inches is better for the size of your sump. You can adjust the flow by adding a tap or valve. This will adjust you flow and water level accordingly. HTH

Cheers, David

[Ash]

um, you need to stop the siphon on your return line, so either put it higher (weir height) or whack a hole into it above weir height but below running height so it breaks the siphon - then fill the tank/sump as per reillin/baz

cost = 10sec with a knife/skewer

edit: oh wait, is the return drilled? Doh!

[romak50]

Thanks for the advice guys - and yep, Ash, its a drilled return!

[CAL.16V]

ive got an irrigation tap so when you want, you can turn the water off from coming back into the sump and also have a big one way valve after it so if your not around to turn the tap off, it wont come back past it anyhow.. my return is about 20cm of teh bottom of the tank and hiden by rockwork, cut it down from the big pipe it used to be as you dont need it wiha one way valve as it dosent drain back..

[Ash]

no option but a bigger sump then I guess