Water butt syphon
clarke.brunt Posts: 215
edited March 2021 in Tools and techniques
I'm lucky to have the space for 6 water butts. Just though I'd relate how easy it us to rig up a system to syphon water from one to another so all remain at the same water level, and it doesn't matter which one you draw water from, or which the collected water goes into, since it will be replenished from the others.
Rather than connecting them with pipes at the bottom (imagine what happens if one of the pipes falls off...), or the 'overflow kits' where a pipe connects holes near the top (only works as an 'overflow' - doesn't syphon back the other way), I use lengths of hosepipe as syphons from one butt to another (I'm definitely not the first to do this, but it works so much better than I'd hoped).
Get all the water butts at the same level (the water will eventually overflow from the lowest one). It's very helpful if you raise them off the ground, so you can get e.g. a watering can underneath the tap, and it lets you use the water right to the bottom. I've found that the plastic 'stands' available tend to collapse after a year or two - I use old breeze-blocks and bricks to get the correct level. Now get lengths of hosepipe, long enough to reach from the bottom of one butt, over the top, and down to the bottom of another butt. To 'prime' the syphon (i.e. get the length of pipe full of water, with no air) it's easier if at least one of the butts is already full. You can suck on the end of the pipe (risk of mouthful of water, as I got yesterday), or use a mains-water hose to fill the pipe, or just dunk it all below water level in a single butt. Then place your finger over the end, and release it near ground level - ensure water is flowing and any air comes out. Re-apply the finger, and lower pipe into destination butt - only taking your finger off when lower than water level in source butt. Repeat as needed to connect other butts.
Sounds a faff, and I thought I'd be having to get the syphons going again every few weeks, but no - it's very rare. Maybe once a year, one gets blocked by debris or gets air in and I have to sort it out. But otherwise it just works. 3 of my 6 butts actually collect water (2 sides of greenhouse, plus another building); only 4 of 6 have taps on them; and I don't need to worry which one to take water from, since it's automatically refilled from the others.
All this lot is primarily for a load or carnivorous plants, which demand rainwater. If enough spare after that, then used in the greenhouse and on other plants as well, or even to top up the pond. I find that 6 butts is about right for me - usually lasts over summer dry spells, and all 6 fill up very quickly when there's a rain-storm.
...would it work to tie the end of the hose to a half brick, I wonder?