Dad has an older octagonal spa. Apparently he burned up his heater by using trichlor tabs before the coil or something. So, the spa store sold him a Natural Mineral Sanitizer http://www.nature2.com/ that apparently uses silver to sanitize.
Fast forward to a couple weeks ago, he tells me he's using powder to supplement chlorine. I figure his CYA is through the roof so I sent him home with a test. He reported the dot disappeared immediately. So, he drained and refilled last week, went to camp with the kids and this morning I had him run a full test minus CYA (he's out of reagent).
Since the fill, he's added about 8ppm worth of dichlor. I'm having him keep track of ppm's added with instructions to switch to bleach when he gets to about 30ppm of dichlor.
He also has an ozone system.
This morning's numbers
CYA (assumed 5-8)
He added dichlor to raise TC and FC to 1.75. No CC.
We then raised TA to 80 and CH to 150 (although he didn't retest CH, will check that later).
The spa is under a porch roof, enclosed and protected on the sides with latice and fake stained glass film plexiglass windows. It is not fully enclosed although most weather elements other than wind do not enter the area.
My question revolves around the silver thingie he's got going on. What is it? How does it work? Does it REALLY disinfect? He also has spent years with a systemic MRSA infection in his spine as a result of an infected cadaver bone from spine surgery. 3 years, 15 surgeries, mostly dead the whole time, with vancomyacin in his veins every day. It was gone for about 3 years, came back last fall. Hospital stay, and 25+ more weeks of daily IV vancomyacin. Essentially, MRSA will always be an issue for him and although his infection is systemic my kids and H have battled MRSA skin sores in the past two years as well. We don't know for sure if there was actual transmission, but it's very suspicious to say the least.
The reason his CYA was so high is that he was regularly adding dichlor every day. He would "throw a couple teaspons in" (he likes to use the cap... sigh...). While i'm all for chlorine on top of the silver thing that he says doesn't need ANY chlorine supplementation, I do not know if he should be following the minimum/target/shock recommendations like we do for pools or using lower doses of chlorine. Switching to bleach will stop the rising CYA, he's on board with that plan but I'll need to calculate his daily dosing cuz he's still wanting to just "throw something in" every day to simplify his crazy busy spa soaking time...
We assume his CYA will be around 20 when he stops the dichlor. Should he be dosing to 5 (target) every day, never going below 2, or can he run at his preferred level of maximum 2? Of course he prefers low levels because he has (had) no clue what CYA was and how it affected CL levels. He read once his spa should only be 2ppm max and apparently that stuck. He's working with me on this, although still just a tad set in his ways. i.e. complaining about using up his reagents to test for CH and TA and it's just wasteful... blah blah...
OK dad, and WHY did you buy a total dissolved solids tester on ebay then if you just can't be bothered to check TA and CH? Apparently the Taylor book told him he needed to test it to make sure it wasn't too high. Sorry, just a bit lost on that one. Anyone know much about total dissolved solids? Is this iron? Who cares?
Thoughts are welcome. Am I doing it right for a spa? Temp is 102. My kids get in there with him all the time, I need it to be disinfected properly. MRSA is awful stuff.