08-28-2010, 09:31 AM
A general comment - when I switched over to using RO water, I saw a pretty significant upgrade in plant appearance and vitality. Yes, subjective, but I am very pleased.
Jerry D - I absolutely agree with the tropical fish potential issue, but they are a lot more sensitive than plants, a lot depends, of course, on the construction of the dehumidifier and the rate of dehumidification (i.e., condense a lot of water in a high RH environment, and the metals concentration will be reduced). One might use a similar argument about rainwater, as it does a fine job of cleaning air pollutants and roof sediment.
Jerry-amore is right that a well-tuned softener should not dump excessive salt into the water. A clean, well-tuned gas heater should not put ethylene into the air either. Unfortunately, mechanical things can get out-of-whack easily and without our knowledge, so we go to measures to avoid them being an issue.
The "wasteful" nature of the RO flush water is always up for debate - and a lot of that is determined by just what you do with it. I have two RO systems - one in the greenhouse, and one for the drinking water and ice from my refrigerator. The flush water from the greenhouse used to go on the floor (where it percolated back into the groundwater supply) for humidification, but now goes into an artificial pond that is used for drinking and bathing by birds, deer, etc., and is a home for MANY frogs. The in-house system flushes down the drain and into my septic system, enhancing its function, and again percolating down into the groundwater.
Those are just two ways to use it; there are others, including zero-waste add-ons.
So how much waste water is produced by a softener? There is the backwash part of the cycle that removes dirt from the mineral tank, and the recharging phase that brings in more sodium while flushing the precipitated minerals from the bed down the drain. Some even come with warnings that they can overwhelm a smaller septic system!
Using science and logic
to advance orchid growing