Just a few questions :-D

cant you get siphons that have a pump on them that start the syphon again when power goes out?

Sean

 

dont need to the one on thediy section starts itself again when the power goes on

 

HOB overflows are designed with a wall to prevent it from losing siphon in a power failure. I'm running one and have never lost siphon for any reason. To prevent bubbles from accumulating in the tube and reducing flow keep the flow through the sump high.

You also want to set the level in the pump section in your sump relatively low. This allows water to flow down in a power failure and not flood the sump. This is important in any system, drilled or HOB siphon. If the siphon develops a clog, you only need to worry about the small amount of water in the sump section overflowing the tank. If you set the water level in the tank properly there will be enough head room to prevent the tank from overflowing.

Make sure you drill some small holes in your return pipe just above the water line to break siphon in your return plumbing from your sump pump in a power failure otherwise you will empty your tank in a power failure no matter what type of system you have.

My tank wasn't pre-drilled and I didn't want to risk it cracking. The choice is yours. Both solutions will work fine. If you choose to drill make sure you don't drill the bottom it is usually tempered and will shatter. You'll have to drill a side.

 

thanks for the heads up, vanpyre do you have a link to the diy hob?

 

look in the "i made this" forum and its at the top under nice cheap diy overflow,
I have had this going around three days in a tub in the garden and have made mock power cuts, it has started EVERYTIME, it takes some reading ut it is quicker to make than to read the thread!

 

cheers