Thanks all. I use GH 3 parts with tap water which is PH 7 from the tap. I say that the CO2 is injected into the water as the O2 because of the air pomp, that's all. So you say that it's normal to have a little rise of the PH anyway because of the roots job ? OK, i just remember the QUEBUD post where he said that he stabilized the PH once every tank change, and never every day, but OK, i don't stress with that. Thanks for answers. StormCooker, i put my AK47 ladies to flower 2 days after you. So we will compare, OK ?
Fhydro