Jack's Magic Purple Stuff for SWG?

Anyone using this for their inground SWG? My new pool builder recommends this to prevent staining, and the scaling of the SWG cell. I am on my last bottle and would prefer not to buy it again if it is not neccessary. Thanks.

I never use anything with the word "magic" in the name..

never heard of the stuff.

I have used it and it seems to work. However, it does have phosphates in it and will raise your phosphate level very high which can be a problem if your pool gets out of balance (phosphates can be algae food). I stopped using it and I just make sure I stay on top of my pH by not letting it get too high. If you do that, you should have no scale. Muratic acid is a lot cheaper than "The Purple Stuff". This stuff is also a metal sequesterant and there are similar products which do not use phosphonic acid. I would use that if necessary. Anyway, just a few words from my experience.

Mike

If you do not have a metal or staining problem then you really don't need the purple stuff or any other sequesterant. Jack's Magic is one of the better lines out there , IMHO, when a seqesterant is needed. Mkamp1515 is right that it is HEDP, a phosphonic acid derivative that can form orthophosphates (algae food) in your water but very few people ever have problems with algae simply becasue of high phosphate levels.....mine have been between 2000 and 3000 ppb and I have never had al algae bloom! A much better way to prevent scaling of your salt cell is to maintain a proper water balance, don't let your pH get above 7.6 (high pH promotes scaling), and watch your TA and calcium hardness. If you have very hard water (high calcium hardness), then it might be of some use in helping keep the scaling down since calcium is a metal and is seqestered in the same way as copper and iron by seqesterants (but ususally not as much).