kwik tip, make sure when doing water works you keep the water under 75F, 65-68 is best, as for PH it will rise everyday, for instance, your nutrient solution is at 5.5 when you make your mix when changing it out, the next day it will probably be up to 6.5 and 7.5 the day after that, thats how it goes for me, and if you dont keep an eye out for it you will get these issues, make sure you have plenty of PH down at all times your gonna have to keep readjusting, i dont know what kind of testing methods you are using, if you dont have one cus they are costly, get a reliable PH meter, one can be had for less that $40 on ebay from a good company...also get a PPM meter from ebay a good TDS meter for around $25