I've not tried it either, but I do like the fact that they specify their fert should be used with water that has low alkalinity. Mine is somewhat high, so that's why I haven't used it.
Seems to me they used to have a formulation for higher pH well water, too. I'll have to check. I water with my well water which has a pH of around 8 = very high. Even our tap water is above neutral.
Kate you can check the pH of your tap water or whatever you're using, just the same way you check the pH of your pool.
