SF4000 LED - Fast Buds - Purple Lemonade

Ok, lets think about this logically - why are the leaves turning brown? it looks like a Calcium/Phosphorus issue, A LOT OF PEOPLE HAVE THIS , is it a deficiency??? Unlikely in Hydro as the solution is more effective as there are no contaminants, so this leads me to believe its a lockout, what can cause this ? 2 things = A) Too Much Nutrient Potassium or B) ph is too low - SO to rectify this, i have added more water to the reservoir and raised the ph to 6.3 As i am using more water in the reservoir its entirely possible that when the water goes down,even though the EC stays the same the proportional concentrations of each nutrient can change - for example EC pen says 2.0 when i first fill with 20 litres, the plant drinks 4 litres of water and consumes lots of bloom A+B so when i put my pen in two days later the 16 litres of solution still reads 2.0 but there is a higher proportion of PK. Of course it could always be option C) these plants eat phosphorus for breakfast and need more ..😜 I have checked roots they all ok Wednesday- changed solution , made it slightly weaker EC 1.7 ph 6.2-3 Thursday I had a little chat on Instagram with mammoth , i think they might need less than usual Saturday - noticed some yellowing on the little plant , it’s a confusing as th3 other plants are all using the same nutrients and they are loving life , it might be the buckets , I am much preferring the size of the 35 litre ones , and the root structure is perfect , because the 45 litre boxes are more rectangular than square the roots are sort of sideways . Still waiting for some purple on the tall one 🤔 ITS VERY IMPORTANT IN DWC - Do not automatically think you need to add nutrients , in DWC it’s so much more efficient that less is more , 99% of the time it’s overdone it , normally the tips go brown first , but it’s some circumstance s The concentration can increase without you knowing , FIRST change solution with a little bit less , I usually go to 1.6-1.7 EC TOTAL and 6.3 ph that is a universal solution that provides enough without overdoing it . Updated DAILY