Reverse Osmosis Water Filtration System in Hydroponics Greenhouse
One of the most overlooked things when building a greenhouse hydroponics system is the source water itself. Whether the source is from tapwater, ground well, or pond – proper lab testing is required to determine the contents of the source water. The reason is that hydroponics systems, or any growing systems in general, require good quality, clean water. In this article, we’ll show you how we set up a simple RO system on the farm.
Why Need To Use Clean Water?
If your source water on the farm is from a shallow groundwell or from a pond, you can imagine how “dirty” the water is. The source water from a pond or groundwell is full of bacteria, fungi and oomecytes, and different chemical and minerals. Using this source water in your hydroponics system will be disastrous for your plants and you’ll be endlessly adding fungicides and nutrient additives trying to figure out what’s wrong with your plants. But the problems will keep occurring if you don’t address the root of the issue: the source water.
Testing for Clean Water
Testing your water comprehensively can be done at any water laboratory, but you can also do an easy pH & TDS test using an inexpensive pH & TDS meter. Normal tapwater that has been treated at the municipal level is usually at 150ppm with a pH of 7 (neutral). This represents clean drinking water. The lower the TDS in your water, the more pure and clean it is.
REVERSE OSMOSIS WITH MULTISTAGE FILTRATION SYSTEM
In this setup, we have a 1hp submersible pump on a Smart Outlet pulling water into a 1000L IBC tank via a multistage filtration system (FRP multimedia filters, sediment, activated carbon). We used 32mm polypipe with PP compression adapters and fittings. The IBC tank serves as the reservoir of water that has been cleaned, and is considered mineral water.
If you need polypipe or any PP Compression fittings, please visit our shop.
From the 1st IBC tank, we use a 0.5hp electric tank to pull the mineral water into the Reverse Osmosis (RO) membrane and UV germicidal light to store in the 2nd 1000L IBC tank. This water is now considered clean “mineral” water, free from impurities, sediments, and bacteria/fungi. From this IBC tank, the irrigation controller activates irrigation into the growing systems and hydroponics systems in the greenhouse.
We measured the TDS from the pond source at 750ppm. After filtering through the RO system, the water was measured at <50ppm.