IT sounds like the unit that your dealer sold you to go inside your filter well is a Nature 2 (N2) or similliar product. In theroy, it release silver ions into the water, which makes the bacteria more suspetible to the sanitizing agent (I belive it weakens the bacteria's cell wall). In a nut shell you are supposed to be able to use less sanitizing agents (chlorine, bromine or MPS). ie; you can kill more bacteria with less sanitizer.
Additionaly the manufactuer of the product claim it will also "enhance" your water, making it clearer, and "silkier". Your whites whiter. Your breath minty freash.
Some folks claim it reduces male patern baldness. Woman claim an increase of 2 cup sizes.
Some folks here swear by it. I've used it and didn't see any improvement. And yes, the dealer also told me I'd be using less sanitizer, but I was never given a program that called for less sanitizer. Given the cost of the product ($25-$30 per unit) and the cost of Dichlor, I figured for me, using the product was significantly more expsensive than not. But as I said, some folks here absolutey swear by it.
I say, judge for yourself, use the program for a while, and then switch off of it. See for yourself .
I am on a dichlor, and ozone system and shock with MPS, so I'm not an expert in your mehtod, but 2 tbs of MPS everyother day seems to me to be ALOT.
Here iswhat the manufactuer recomends for sanitizing your pool with N2
http://www.nature2.com/spas2.asp
Before Each Use
Add 1 tablespoon of potassium peroxymonosulfate (MPS) to spa per 250 gallons (approx. 1000 litres)
(Note: 1 tablespoon = 1 tablet = 3/4 ounce = 21 grams.) A convenient way to insure proper MPS level is to use a Nature2 Spa Test Strip. If the Nature2 Spa Test Strip indicates a low level of MPS, add 1 tablespoon of MPS to spa per 250 gallons and retest.
Once A Week
Add 3 tablespoons of potassium peroxymonosulfate to spa per 250 gallons (approx. 1000 litres). Check and adjust pH and total alkalinity. A convenient way to check pH and total, alkalinity levels is to use a Nature2 Spa Test Strip.
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The silver ion catridge must be replaced every time you refil your tub. There have been warnings posted in this forum not to keep old catridges in the filter well. They may break, spilling the ceramic beads into the pump causing major, non warenty damage.
Question for the pros:The above method only calls for MPS. Can a hot tub be properly sanitized only using MPS? I was under the impression
some amounts of diichlor or bromine would be needed no matter how much MPS or magic siver beads you use?