first time growing - long time lurker

Hi all first timer growing been lurking a long time. I started these off in November and they are around 6.5 weeks or so old.

Light: Mars Hydro TS3000 (26" off canopy)
7 gallon smart pots
started in FF happy frog and transplanted about 4 weeks ago into OF.
soil ph from blue labs probe is 6.28 at the roots, watering in around 6.4.
temp 74
RH 53-55

I fed half doses of grow big, cal-mag and big bloom about 16 days ago and got slight nute burn and was a little N-toxed. went straight RO ( with nothing added) for 2 waters (getting water every 4 days or so). lollipopped on Saturday and watered with tap PhD to 6.4 fed half big bloom and calmag. started seeing what looks like to be P deficiency with purple stems but possibly calcium? any ideas?

thinking is washed away some minerals/nutes with those two RO waters. not sure if I should flush or just start adding more cal/mag and pk booster? any help is appreciated.

Pic 2 looks like Ca. deficiency.

Nixs said:

Pic 2 looks like Ca. deficiency.

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Thank you for the reply. i just watered with ph tap to 6.6 and took runoff. runoff ph 6.1. I took a ppm with my cheap tds meter and it read 430. getting this calibrated and possibly a new tds meter to make sure that's accurate.

youold said:

Hi all first timer growing been lurking a long time. I started these off in November and they are around 6.5 weeks or so old.

Light: Mars Hydro TS3000 (26" off canopy)
7 gallon smart pots
started in FF happy frog and transplanted about 4 weeks ago into OF.
soil ph from blue labs probe is 6.28 at the roots, watering in around 6.4.
temp 74
RH 53-55

I fed half doses of grow big, cal-mag and big bloom about 16 days ago and got slight nute burn and was a little N-toxed. went straight RO ( with nothing added) for 2 waters (getting water every 4 days or so). lollipopped on Saturday and watered with tap PhD to 6.4 fed half big bloom and calmag. started seeing what looks like to be P deficiency with purple stems but possibly calcium? any ideas?

thinking is washed away some minerals/nutes with those two RO waters. not sure if I should flush or just start adding more cal/mag and pk booster? any help is appreciated.

Click to expand...

Phosphorus deficiency

Is it possible to get your temps up a bit? cannabis under LEDs almost always prefers tempsnin the low to mid 80s. especially during veg through mid flower.

NanoGadget said:

Is it possible to get your temps up a bit? cannabis under LEDs almost always prefers tempsnin the low to mid 80s. especially during veg through mid flower.

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I can try. the issue I'm having is weather outside is so sporadic that it messes with my grow room. today its 15 degrees outside...thursday it will be 50 outside. ill try getting it up a little

hotrodharley said:

Phosphorus deficiency

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that's what I was thinking as well. that or calcium. i have some bone meal I can top dress with or I also have a pk booster. might try adding a little p on my next water