Hi Guy

ive grown 4 crops now indoor in rock wool under 600 HPS 18/6,
i hand feed every day the same as every other crop... i
perfectly balance every thing from nutrients to PH set up 6.2....

The probelm is

The water run back into tank and the PH is through the roof
at 7.6 now this has happen pasted 2 crops, i drop it down
and have flushed it but still sky rockets, ints in week 4 of
veg and they look like there in week 1 with no growth, tank
is filled everyday fresh and temp of water is good with air
stone inplace also, good air flow through also...man ive had
enough, what can it be.... i have also added bactia kill to
clean out any bacteria problem an now ther is a Red residue
in tank, please help..

kind regards

Darran