Help me diagnose what's wrong (2nd week of flowering)

Hello everyone

Hope someone with experience could help me diagnose my lady here
Medium : premixed soil with added compost and perlite
Pot size: 8 gallon
Starin:unknow, it was from a bag of seeds
Light :300W HPS
Stage: second week of flowering
Water frequency : around a gallon every 3 days
Ph:Not sure about this one (definitely could be the problem here and my ph test kit is broken now)
Usually i use tape water or RO water with a some drops of ph down solution.
Now at the beginning of week 2 of flowering, my plant stopped growing and the top leaves started to be light green with stunted growth.
Also I'm observing these yellow/brown batches here and there.
And sometimes i find a lone yellow leaf at the bottom of the branches (not frequent)

Would really appreciate your advices here.

Usually 2-3 weeks into flowering, the plant stops growing upwards and starts working on producing flowers. Are you feeding cal-mag at all? The ph could be a problem but it looks like you need to feed some calmag.

TheSadBadGrower said:

Usually 2-3 weeks into flowering, the plant stops growing upwards and starts working on producing flowers. Are you feeding cal-mag at all? The ph could be a problem but it looks like you need to feed some calmag.

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It's started to happen at the very beginning of week 2 (3 days ago) and i fed with cal mag the last time i watered (2 days) ago, i though cal-"mag would solve the issue in a day or 2 but I'm not noticing any progress

Your plant looks pretty healthy. I wouldn't worry about a few blemishes here and there.

FlowerPower001 said:

Your plant looks pretty healthy. I wouldn't worry about a few blemishes here and there.

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It's just I'm afraid the minor changes happening could be a sign of underlying problem.
Like she had this same "pale" growth all over when she needed a transplant (i scratched on this possibility now as i don't see any roots coming from yhe drainage holes or anything)