N or Mag deficiency, other, or normal?

[cr8grow]

Leaf tips browning, curling up...moving up the plant...buds not impacted (yet?). Larger brown splotches I attributed to water/nute splashes from watering when pulling up long-neck funnel. I added pics with flash from this morning, including a top down view of all 4 plants and some closeups. For the separate leaf pics, the real bad ones are from below and I wasnt that concerned...the “better” ones are the issue, in particular the top 2 “greener” leaves are representing my primary concern. Also just noticed the leaf stems are reddening up.
Read threads here but cant confirm condition, which may be OK for this stage of flowering? Plants look pale under 3100k light and not very lush...hope flash helps.
First grow, indoors...fem. GSC from Nirvana. Day 1 week 11, start week 5 true flower (Nirvana suggests 7-9 weeks flowering).
Soil Roots Organics 707; amended perlite, worm casings, silica
Light CMH 315w 3100k at 24 inches above canopy.
Temp 64 - 81
RH 40 - 35 (30 when ready for water).
Passive air intake (through Hepa filter and light box)...4 inch exhaust fan with carbon filter runs 24/7...two small fans for airflow, one below and one above the canopy.
I see a few fungus gnats occasionally, adding 1 tsp. Mosquito Bits to each watering...doubled to 2 tsp. last week.
Water PH 6.5 after nutes. Watering 2 gallons across all 4 plants every 3-4 days with flowering nutes. Feeding each watering. Nutrients per gallon - Superthrive 16 drops (stopped adding week 4), Budswel 1 Tbsp. Biocanna Flores 2.5 tsp. Molasses 1 tsp.

 

[cr8grow]

Added another pic of bud closeup with slight purple coloring, which is normal for GSC...not sure if that could also indicate a deficiency. No more vertical growth...lights stationary now 2 days. Pots are still heavy...plan to let them get pretty light before next watering.

 

[TurboBucket]

They don't look too bad. A little light on N maybe. The lower stuff tends to change color and fall off as they age, the tops are the best indicator. It seems a little early for purpling but with 64 for a low it's certainly possible.

I do agree they look a little off though

 

[cr8grow]

They don't look too bad. A little light on N maybe. The lower stuff tends to change color and fall off as they age, the tops are the best indicator. It seems a little early for purpling but with 64 for a low it's certainly possible.

I do agree they look a little off though

I really appreciate the feedback from an experienced grower. For some reason I began to overwater the last few times with lots of runoff...which I cleaned up each time. I also didnt let the pots get light enough between watering...just got lazy I guess. First strategy is to let the pots get almost dry watching for slight lower wilt and light pots...going on day 6 with no water...which indicates how heavy handed I got on watering. I will need to water thus weekend. 2nd strategy which may be a mistake...I mixed a 1/4 strength tea of Dr. Earth organic Homegrown fertilizer. To that I will add 1 Tsp epsom salts. I will water the first gallon across all four plants with flowering nutes same as normal. I will then add nutes to the 2nd gallon with the tea and mag and only use as much Slowly until slight runoff. I think I starved my plants at the end of veg and also stressed out the plants by lollipopping under the scrog. I did cut out the scrog...wasnt ever really needed with my LST...so I can flush and dry out again if thats the better first strategy.

 

[MrSauga]

If I can chime in a bit as well I would also say you have a mag def from everything you described and from the images of the leaves you pulled off. Your environment sounds fine, albeit the RH a tad low when you hit the 30's, but I suspect you have an imbalance of nutes right now. The light color is due to the mag def and not so much an N def. N def alone would produce interveinal chlorosis while the leaf turned yellow, eventually turning yellow completely throughout the vein and dropping off. Yellow leaves dying off from the bottom with the browning that you see thoughout the leaves is indicative of mag def.

So imho, you need to find out what causes your plant to demand more Mg or what's reducing the availability of the MG.
Too much N and/or P in your mix increases the demand for more Mg, while too much Ca and/or K reduces the availabilty of the Mg.

To get a correct balance try and shoot for an NPK ratio of 23 which should clear up the issues you are having.

 

[cr8grow]

I received my EC meter and tested my well water this morning. I dont know what the numbers mean exactly other than I have a high value of TDS. Ppm is 149 ( in the red on the meter) and EC is 319. My tap PH ranges around 7.5 and drops to 6.5 when I add Biocanna Flores and Budswel guano tea. I know I underfed in veg after one nute burn scare, which actually was minor. I also then flipped to 12/12 soon thereafter and went to flowering nutes very low in N and the chopped the hell out of my plants below the scrog. Scrog has been cut out and removed for intervention and care purposes...I can pull plants out of the cabinet again. Perhaps my nute lockout is from excessive watering...just went 6 days with no water in a dry out cycle. The plants are not drooping yet but pots are light and I will water very carefully this morning. The plants dont look any worse and the buds continue to swell and are becoming very frosty. Going into week 12 I will do another diary update Sunday. First gallon will be usual flowering nutes Biocanna Flores and Budswel guano tea. My plan is to add a VERY weak organic fertilizer tea and epsom salts to the second gallon of water + flower nutes and will water very slowly until just a trickle of runoff. I will then wait until the pots are light and ready for the next watering. I also bought 4 vinyl coated mesh wire suet feeders...works perfectly to raise my pots a bit for better air flow below the pots.

 

[cr8grow]

Day 76, end of week 11, end of week 5 true flower (tomorrow). Heres what I decided to do this week. 1) calibrate my PH pen...spot on. 2) I was overwatering on a routine...RH drops to 30 time to water...not waiting for the pots to get light...I let the plants go without water for 6 days to dry out, not to the point of wilt...was way overwatering. 3) watered yesterday...1st gallon across all 4 plants with usual Biocanna Flores, Budswel and reintroduced Superthrive...PH 6.5. The 2nd 1/2 gallon across all four plants included 1/2 strength Dr. Earth Homegrown organic fertilizer tea and 1 tsp epsom salts...PH 6.8 so I didn’t add flowering nutes. No runoff, but the pots are heavy...stopped there for this rehydrate. I also didn’t add any molasses this week. Plants don’t look any worse this past week and hopefully my intervention doesn’t make things worse. Pots will be light again before I water...then back to regular flowering nutes. I have 2-4 weeks left to flower...will be checking trichomes for ripeness...will not chop early unless I run into a major issue. Good news is the buds look great, fattening up and getting frosty with hints of purple. I added a picture of my new mesh pot raisers to air out between pot and saucer...vinyl coated bird suet feeders.

 

[cr8grow]

Day 83. End of week 12, end of week 6 flower (tomorrow). Watered two days ago after 5 days no water...pots were light but no wilt...watered slowly and used 1.75 gallons across all 4 plants (up from 1.5 gallons last watering) evenly til just slight run off. Still in intervention mode but with about 2 weeks left I think I will make it. 1st gallon 2.5 tsp Biocanna Flores, 1 Tbsp Budwel guano, 16 drops Superthrive...Ph 6.5. 2nd gallon same plus 1 tsp epsom salts and 1 tsp molasses...used 3/4 of that gallon...Ph 6.3. I do not plan on using any more molasses or epsom salts the balance of the grow. Im also going to run a test to determine if it was the epsom salt, molasses or both that took my Ph from 6.5 to 6.3...not much but I want to know going forward.