Drain to Waste: An Introduction to Hydroponic Systems

Drain to Waste: An Introduction to Hydroponic Systems

Hydroponic systems come in many shapes, forms, and sizes. The operation I grow with could be considered micro-scale production. We grow too much for a family to eat, but not really enough to feed a crowd. Our facility has a number of different hydroponics systems, and in this article I will break down one of them: the drain to waste system.

Pepper plants in the drain-to-waste system

In this system, nutrient solution is pumped at high pressure from a reservoir, through the piping, and is trickled in to the base of the plant. As the name suggests, the nutrient solution that is pumped to the plants is drained at the end, rather the re-circulating back in to the reservoir. Though this may seem wasteful, such a system has it's advantages. As the water is never circulated between the same plants, it is impossible for the water to transmit disease. Additionally, the nutrient is always fresh and in balance.

Of course, the downside is waste. At its current settings, this system uses about eight gallons of solution per day. In order to limit waste, the pump is attached to a timer, which fires five times per day for three minute intervals. Though pumped at pressure of 20 psi, the design of the feeders ensures that only a trickle is actually dropped at the base of the plant. The large pump and high pressure are necessary to ensure that plants at the end of the line receive the same amount of solution as those nearest the pump.

The injection feeders are driven in to the plant's rockwool foundation

After the solution drips through the roots and growing medium (in this case perlite), it drains to a PVC pipe though a hole in the bottom of the bucket. The PVC is open at one end. Gravity draws the used solution though the pipe, out the end, and to the drain.

Though less practical for home-hydroponic growers, the advantages of the drain-to-waste system make it a safer bet for commercial growers, especially when growing crops that are susceptible to water borne disease. Ironically, peppers are not one of them, but that's what we have in the system right now.

For those that are curious, the plant in these pictures are about 6 weeks old. I anticipate that that will start flowering in a week or so and putting on fruit a couple of weeks after that.

I hope you have enjoyed learning about the drain-to-waste hydroponic system! I will answer any questions I can in the comments. If you have enjoyed this post, keep an eye on my blog as I will introduce more hydroponic systems in the coming days.