myvols2002 said:
I got a 24ft above ground pool with a vinyl liner. My ph stays at 7.6 and alk at 120 and my clorine stays at or near 0. I never had to add anything in 4 years to adj this. I just add shock and clarifier every two weeks. The ionizer not only adds copper to kill algea but also silver to kill bacteria.
Thanks for the info. The vinyl liner makes it less likely to have staining problems (plaster surfaces continue to be at higher pH due to continual slow curing) and in any event your pH is stable which is important. As for kill times, at least you have both copper and silver with your ionizer (where does it say that Perma-Salt uses copper and silver rather than just copper only?). That does at least help to kill fecal bacteria which copper doesn't touch at all at pool concentrations. However, see the chart in
this post for the truth about kill times with copper and silver vs. chlorine (with CYA). So having at least a small amount of chlorine in your pool is still a good thing since it not only kills bacteria more quickly, but also kills viruses that copper and silver typically don't handle. So while your "near 0" as in a low chlorine level of even 0.5 ppm is one thing, having it at zero is something else entirely.
That leaves oxidation of your bather waste so that you don't soak in the ammonia and urea of your own sweat and urine. It sounds like this is getting handled by the shock and possibly by the clarifier. Are you using the
Perma Salt Klairate Natural Enzyme clarifier? Are you finding that the water gets too dull/cloudy if you don't? Why is the chlorine level ever at zero -- are you not adding any other than from the shock?
Anyway, if one is going to be using a metal ion system to run at lower chlorine levels (not zero levels, however), then a copper/silver combo is the way to do it and if you are having a controlled pH and your shock doesn't have the pH rise then the risk of staining is lowered. What are you using to shock? With your TA level, it's probably not a hypochlorite source of chlorine like Cal-Hypo, chlorinating liquid or bleach. Is it non-chlorine shock (MPS) or Dichlor or Trichlor (granulated)? Or are you using
Perma Salt Activate Shock Treatment which is a combination of Dichlor and Oxone (MPS). If it's Dichlor and Oxone, then that explains the fairly stable pH since these are acidic so compensate for any pH rise from the TA so eventually you get to a TA level where pH is fairly stable (though over time the TA will fall unless you have evaporation and refill to increase it).
What you are doing is not allowed in any commercial/public pool because you said you are sometimes at zero chlorine. The lowest allowed chlorine level with a metal ionization system that can still be claimed as EPA approved is 0.4 ppm FC as shown by
these NSF Standard 50 products which, by the way, does NOT include Perma Salt. If the chlorine gets below that level, even with the metal ions in the water, there can be person-to-person transmission of disease. In a residential setting, this is obviously a lower risk since one infected person entering your pool can't infect dozens or even hundreds of other people since the pool simply isn't that big.
However, if you are only shocking once a week, then the Dichlor isn't going to last more than a few days so the rest of your time your pool does not have an EPA-approved disinfectant in it. One bag (which is one pound) of Activate in 10,000 gallons would be 6.6 ppm FC if it were only Dichlor so it's probably more like 3 ppm FC chlorine and the rest MPS. While having the copper/silver combo helps prevent uncontrolled bacterial growth, your pool is not safe from person-to-person transmission of disease and quite frankly you are ingesting far larger quantities of live bacteria from fecal matter than in a pool with even a very small amount of chlorine. You are simply fortunate enough to have a robust enough immune system to not get overwhelmed by your own or other's fecal matter. Remember that the kill time for copper/silver vs. chlorine for most bacteria, including those in fecal matter, is 50-200 times slower. While just fast enough to prevent uncontrolled bacterial growth of many of the bacteria (but
Staphylococcus aureus is on the edge), it is certainly not fast enough to prevent person-to-person transmission of such bacteria during swimming and does nothing for viruses entering into the pool. Of course, realistically, you're probably just swimming with your own family and at least for the viruses have other more common routes of exposure.