NOTE: This is in response to a post that was subsequently removed. It extolled the claimed benefits of Nature2 while ignoring the potential risks. My response below challenged several of the assertions in that post.
JARBS said:
The way the N2 system works is that it introduces copper & silver ions into the water.
This will eventually lead to metal staining and/or green hair as others have stated. The latter is erroneously blamed on chlorine. Once the metal stains develop, then you must go through extra steps (and expense) of removing them.
JARBS said:
Next install the N2 system super chlorinate with calcium hypochlorite.
Super chlorinating with cal-hypo will potentially add scaling to the mix of issues the pool owner will have to deal with, again causing extra time and expense to remove.
Now, on a seasonal pool that is winterized, it may take longer for these problems to develop. But they eventually will.
Chlorine is often mistakenly blamed for a variety of issues such as the green hair mentioned above and faded bathing suits. Much of the fading of swimwear is likely happening in the washer than in a properly chlorinated pool. However, if someone is bent on running at a lower chlorine level, they would be better off using a supplemental dose of Polyquat 60 as
chem geek stated. At least that approach doesn't have the side effects of the metal in Nature 2 and other algaecides. However even this approach is not considered best-practice because it is more expensive than simply maintaining proper chlorination. Chlorine by itself will keep the pool sanitary without the use of anything else, so I do not understand why anyone would go through the extra expense of adding unnecessary chemicals/devices that will not provide any upside potential.
chem geek said:
Remember that with CYA in the water, the active chlorine level is very low with the minimum for non-SWG pools having the same active chlorine as around 0.07 ppm FC with no CYA.
This is a key point, especially to those who are "chlorine-phobic." To put this in perspective, 1 cup of 8.25% bleach in a 40 gallon washing machine = FC of ~133 ppm and there is no CYA in the washer.
Since switching to BBB two years ago, I spend less time maintaining the pool, fewer $ on electricity by running the pump less, and my swim suits and goggles are lasting much longer. The calcium ring that I inherited from the previous owner is gone. My pool has never looked better.
Given all these risks and reading/hearing about the experience that others have had with N2 and the potential side-effects that are likely to develop, I'm not seeing how this will reduce pool maintenance.