I keep saying: Look how much the Nature2 cartridges cost and you need a new one every season--they start at $90.

That easily buys a season's worth of bleach--plus you have to add bleach to chlorinate it anyway--even if it works as they say. You can usually buy 5 gallon carboys of 12% liquid chlorine for $12. $90 buys 7.5 carboys at that price, or 37.5 gallons. Since each gallon of 12% is the equal of 2 gallons of 6% (ultra bleach) that's 75 gallons. That's the equivalent of 86 gallons of regular bleach (5.25%). If you need that much in 3 months (June, July and August) you are doing something wrong. If you need more than that in a 5 month season, you are doing something wrong.

So when they say it saves you money it is pure, unadulturated swill...The simple arithmetic proves it. If, say, you save half your chlorine expense--that leaves $45 PLUS the $90 on the Nature2 Cart. How is $135 less than $90?