California Growers Under Pressure to Reduce Water Waste
California marijuana growers are under pressure to reduce water use. The legal medical marijuana industry has been under increasing pressure from water providers to reduce water use. Many indoor growers use reverse osmosis systems to eliminate chemicals and minerals from water. Yet reverse osmosis systems are known to use 3 to 4 gallons of process water, sometimes referred to as ‘waste water’ for every gallon of water produced.
Reverse osmosis systems employ a membrane to produce pure water. This can includes chemical compounds not removed by filters, dissolved solids (aka the minerals in water), and metals. That process involves pushing the water through the membrane while a second stream of water continually washes the membrane. It is this second stream of water that is considered ‘waste water’ by those who don’t understand the process. I call it process water and see it as necessary for achieving the goal of purification.
The entire point of using reverse osmosis for treatment is to remove contaminants that can’t be removed any other way. The result is pure water to which can be added the nutrients that growers want in their water.
But what many growers fail to do is to identify the contaminants in their water to begin with and then determine the type of filtration that will best suit their needs.
In many cases reverse osmosis is not needed
Many growers employ a reverse osmosis system when one is not needed. This results in wasting water and paying higher water bills, thus increasing the cost of their grow.
In many cases the primary issue of concern is that of total dissolved solids, or tds. These are the minerals in water and consist of calcium, magnesium, sodium, potassium, and more. A low level of tds, say below 300 parts per million (ppm) is quite acceptable for growing marijuana. However, higher levels of tds are not. And at a certain point tds with high levels of hardness (ie. Calcium and magnesium) become a serious problem. Contaminants like arsenic and uranium may also require reverse osmosis to remove.
California growers are under pressure to reduce water use.
In much of the state this is easily accomplished by using Sweetwater’s Bud Booster in place of reverse osmosis.
What you need depends entirely on your water source. In the San Francisco Bay Area my Bud Booster will remove chloramine and fluoride. Local tests show complete removal of both. Because your water source is the Hetch Hetchy, ie: either snow melt or rain, the tds is very low. The Bud Booster is also appropriate in the Seattle area and western Oregon.
In Los Angeles with a water source of the Colorado River the tds is very high. Southern California water contains uranium, other radioactive metals, and wide variety of unregulated contaminants. In this case I recommend reverse osmosis for treatment.