I checked plants monday and they were perfect, changed nutes, went up again thursday and tips of leaves were yellow n crumbling and roots not too healthy yellowing n coming away, this happened a few months ago but at a worse state (think i caught it in time this time) i had moved to new house but in same area but new house only up a year, my ph meter had broken so ph wasnt tested in water in new house i was just guessing cause been in area before, but had a word with local shop owner n was told could be nute block and to check ph immediately so got new ph meter n ph was 7.5 added nutrient that had used on monday and mixed same way and ph was 3. I now have the plants in water with ph set at 5.5, could some1 please tell me what to do next? i have been growing for quite awhile but have never had this problem till i moved to this house with no ph meter!

Word of warning - Higher water temps mean that oxygen holding capacity is poor.

Use some liquid oxygen without adding nutes. Make it 2 or 3 times as strong as they suggest and get yourself something called AU60 (i think thats the name - red and gold bottle from growshops) which rebuilds roots.

I had a root rot problem in oxy pots a while back and instead of ditching, i sat the affected ones in strong h202 for a week (without any airstone or air pump)

I expected the plant to die, but after the week was up, the roots looked nice and clean and fluffy while the ones I hadnt touched were falling over and wilting. The h202 looked as though it had eaten the dying and dead roots.

I havent done hydro in a while but Id use h202 as life support until she gets back on her feet.

Id use 2 or 3 times the recommended dose with a top up midweek.

or try cannazyme one or the other NOT both at the same time but if ur temps are high and your pots are black then cover them in white. id still leave the airstone on as lack of air was what caused the problem in the first place