What can reverse osmosis systems do for growers?
The reverse osmosis system in this video is a large system for a fairly large greenhouse, but the principles used are the same as smaller filters.
Basically, the reverse osmosis filter is a membrane through which water is pumped, filtering water at a molecular level. Most dissolved solids can’t get through the membrane. This means that the water coming out of the filter is much closer to pure water.
When to use a reverse osmosis system
Reverse osmosis filters are the most reliable solution to correct bad source water quality. The primary culprits of low source water quality for hydroponics or aquaponics are carbonates.
Carbonates act as a buffer. This means that they dissolve into and precipitate out of a solution within a pH range of about 7.5-10.
Unfortunately, carbonates are also basic; when they dissolve (or “precipitate”), they raise the pH of the solution.This makes lowering pH more difficult for growers.
Having a high ppm of salts (they will mostly be carbonates) in your source water to start also interferes with the nutrients you are able to add to the solution.
Read more at Upstart University