Since you are using mineral water, it's probably safe to say that the minerals in the water are buffering the pH up. You don't want to use mineral water. Try using tap water and, if that doesn't work, use r/o water - but not mineral or distilled or carbonated or anything fancy, just plain H2O.

And, if want to be real dro, you need to start checking and, if necessary adjusting, your pH 2-3 times per day at least. Really, screw that light-weight infatuation crap, we're talking nothing less than obsession here.

...and as long as you're adjusting the pH, you might as well try to get it to the correct level, which is right about 5.7

Enjoy your grow. :thumbsup:

PC :smokin: