Timer on IBC tank?
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?
Carmarthenshire (mild, wet, windy). Loam over shale, very slightly sloping, so free draining. Mildly acidic or neutral.