Timer on IBC tank?

Emerion

We’ve got a solar-powered pump rain-watering our polytunnel from an IBC tank, using a timer to run it at 3am. It works well except that as the IBC tap is permanently turned on, the drippers are dripping when the pump isn’t running, very slowly but constantly. It’s surprising how much water is wasted like that. This isn’t practical as summer approaches because 1) the drippers aren’t dripping evenly, some not dripping at all. 2) water dripped slowly during the day when the polytunnel is roasting at 40°C+ will just evaporate. 3) we’re quickly running out of water to let the pump run. An easy solution would be a new timer on the IBC tank to turn off the water for most of the time. But we can’t find any to fit anything but a tap. We would like to be able to go on holiday in the summer for more than a couple of nights and not come back to dead plants. The polytunnel is some  distance from the house, so getting mains water out there would be a biggish job. Plus I want to use rain water. Any ideas? 

wild edges

Do you have to run the pump from the tap on the tank? The pressure is what's causing the leaks I imagine so if you could pump from the top that should relieve the pressure.

Topbird

Can you replace the IBC tap with one you can fit a timer to? If you Google 'IBC fittings' there seem to be taps available that look more like domestic outdoor taps or which come with Hozelock type connectors.

Emerion

Hi, @Topbird. We found a few that looked that they would fit but, on closer inspection, they all need a proper screw-thread fitting on the intake side. None of them had a Hozelock fitting on both sides, or other fitting that would adapt to an IBC tank. Thanks also to @wild edges, that’s a thought. We are now thinking about weighting the end of the hose with a brick and some cable ties, so that it sits near the bottom of the IBC tank. 

wild edges

Emerion said:

We are now thinking about weighting the end of the hose with a brick and some cable ties, so that it sits near the bottom of the IBC tank. 

I've used a length of plastic plumbing pipe for this in the past. Cut a notch out of the bottom and just thread the hose down through it. If you cut it just a bit longer than the height of the IBC you can wedge it in place inside the tank like a central strut. You can fit mesh over the plumbing pipe to stop debris being sucked into the pump if needs be.

steephill

Any of these useful? https://www.dvcontainers.co.uk/category.asp?catID=14

Emerion

What is the benefit of using the plumbing pipe @wild edges? Do you mean the blue, one inch’ish wide stuff, or the thicker white waste pipe? We’ve got some of the blue stuff, but it’s really bendy, having come on a huge reel. So I’m thinking it would be tricky to get it to form a central strut as you describe.

Emerion

Those look good @steephill, and I’m keeping it in reserve, thank you . At the moment, we’re fancying the hose through the top method as it’s less equipment and joint parts to go wrong whilst we’re away from home.