12/12 from start and problems once started to flower

Hello,

started 12/12 on 223w florescent light then switched to 140w hps week after flowering. im a noob so used miracle grow soin with seed starting, feed with miracle grow. noob and dont measure ppm or ph or ec. used filtered city water and have had a few gnats seen (gonna cover soil with sand). i feel like im not feeding her enough and shes got a P maybe N deficiency. pics suck but the leaf died odd with like almost a brown decay then the leaf dying, the next leaves up ar yellowing consistantly and are starting to curl down at the end of the leaf.

Pics below








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thats probably the problem...you dont know the ph balance of your water dude???it suppose to be between 5.3-6.3 im a new grower too bro so hit me up anything to help go check out my 220w thread its from a good ass bag seed strain 13 days in flowering and i saw the first hairs last night

for the p and n get some mg organic bone meal and blood meal ive never had that p and n problem not once