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Kicked the week off with a bit of a watering - 500ml of RO water with 5ml/l root stimulant. For the past couple of days I've notices a slight clawing and yellowing to the tips of some of the leaves emerging from the top growth. I wasn't sure what to make of it at first but suspect it's nitrogen toxicity because she's a deeper green colour than the two photoperiod plants she shares the tent with. I understand the soil mix I'm using is pretty hot, so no additional nutrients until she flowers. Not too worried at this stage, it only seems to be affecting a couple of leaves at the top. Day 23 I just let her do her own thing, then watered again on Day 24 the same way I did previously. Added another pipe cleaner to the main stem to bring the main growing tip down - it's now just a touch higher than the other branches that are now appearing from the nodes. The ends of new growth leaves continue to turn a bright yellow colour. Not sure quite what's up with her. Could be light stress because it hits the higher leaves worst. Adjusted the height to 24 inches on Day 26 and gave her a good watering with 1ltre of straight-up RO water. Day 26 UPDATE. My soil had turned hydrophobic! Rookie error. Turns out I'd let the soil dry out too much and it wasn't holding much at all. Whenever I watered it there was always a good amount of runoff, which I mistakenly assumed meant I'd watered enough. No, it was just running down a couple of channels in the soil and pissing straight out the bottom. No matter how much I tried to water the top of the soil it kept refusing to take on water so I resorted to slightly more drastic action - I gave them a bath. The bath was filled so the bottom half of the fabric pot was half covered, then left her there for 15 minutes to wick water up. Seemed to do the trick and now all the soil is wet through. I let her stand for a bit to drain any excess water out and took a reading of the runoff. pH was 6.6 and TDS 1000ppm, although the TDS is a bit higher than I'd like. She's back in the tent now and hopefully this will help with future watering even if it doesn't solve the problem causing the leaves to yellow, but I'm pretty sure most of that is light burn. Back on track for the end of the week. Happier the soil is now taking in water, but suspect she's had enough water in the past few days to last her half way into next week - slightly overwatered if anything but I reckon she'll pick up soon. Bit of light defoliation down at the base of the plant on Day 28 to remove a couple of leaves. Other than that she seems OK for now. Onto flowering...