FastBuds CBD Crack and G14

Day 29 (2020-06-07): Changed out reservoir (5.6 PH). Picked up some 3% H2O2 so added 3ml/gallon to help combat some of the growth I am getting. Also wiped down the outside of the fabric pots to kill the mold. Did some new LST and defoliation to even things out. CBD Crack is in pre-flower. The G14 might be a bit behind. Day 30 (2020-06-08): Reservoir PH around 5.65. Removed a leaf or two and did some tucking. Day 31 (2020-06-09): PH at 5.8. The G14 Blumat drip tube had gotten stuck in the dirt and was not dripping. Hand watered back to normal. Some slight LST adjustments to even things out and removed a few leaves. Day 32 (2020-06-10): PH at 5.96. Yellow leaf tips on newer growth haven't really gotten any better. I am also noticing some other yellow and brown spotting on older leaves. I am not as worried about the spotting since it is likely related to previous PH fluctuation that has been taken care of but I am now wondering if the yellow tips are something new. Maybe the start of nutrient burn? I do not believe it is light related since I adjusted this a few days ago. Day 33 (2020-06-11): After some helpful advice from the community I checked the calibration of my PH pen and found it off by about .5! This must have happened sometime in the last week or two but would explain the issues since as a result my PH was adjusted way to low (around 4.9 to 5). FIxed pen, flushed plants and changed out the reservoir. Hopefully things will get back on track. Also took the opportunity while I had the plants out to even out the LST and do some more defoliation. Day 34 (2020-06-12): Things are looking OK. I am not sure if the yellow on the tips will go away but it is not getting worse. Reservoir PH is at 5.75. Day 35 (2020-06-13): Res PH at 6.1 but slight smell. Probably will have to change out tomorrow. Things are looking good for the plants. G14 is definitely behind on flowering compared to the CBD.