i am affraid also...
so, because i was using only biobizz products in all my previous grows i did not bother to measure the pH...and except in the first one-two weeks of a plants life, when almost everyone has a too high pH lock out, i didn't had any problems of the sort...
but now that you asked TaNg, and since i am using AN nutes i've got me a pH meter today and did some measures...
my tap water is 7.5
tap water with nutes is 6.8
Brita filtered water is 6.5
filtered water with nutes (the one i use) is 6.1
and because i used neem twice i mesured this also - filtered water and neem is 6.3
filtered water, nutes and epsom is 6.0
and the runoff i got from using filtered water and nutes is 5.9
maybe i am on the down side of the soil pH perfect...maybe i need to stop using filter and lower a bit the amount of nutrients i use...
here are some pics with better light from today...the new growth looks ok i guess...