This post is intended to help those building their own high frequency fertigation system per instructions at cocoforcannabis.com. Those instructions work well, except somehow missed fixing a siphon issue. If you have a tall reservoir like me, there is a pump moving water up a tube and over the lip of the reservoir then down to the grow tent.

What happened was the water would siphon out through the system until the water level in the reservoir dropped to the level of the drip halos. In my case that could be about 8 gallons.

The solution is very simple. You need to poke a hole somewhere to break the siphon. Logic dictates it be:
A) above water level
B) inside the tank.

Here is a picture of the water supply tube coming up from the reservoir.



Notice that I have poked a small hole in the tube. I have inserted a drip irrigation system drip emitter into the hole. Why? Because I had one left from my yard sprinklers so I jammed it in the hole.



Now when the pump runs, a few drops come put and drip back into the tank. When the pump shuts off, air comes in and breaks the siphon.

You only need a tiny hole, not the drip thingies I stuck in there.

Bonus: how to program that Nearpow timer. If you wonder why you set this timer and it skips your schedule, check this.


My index finger points to OFF. If you manually turn your pump to On to pump water, then Off, then press Mode to go back to Timed mode, you will not see anything there. You must press Set, then Confirm to get back to Timed mode.