Day 34, Calcium excess? deficiency? Phosphorous deficiency? Nutrient lockout? Halp! First grow! Had a few pollen sacs as well, no sign now

TL;DR: My tapwater is really hard. I use pH down on it now. So, I am wondering, is this excess of calcium (or something else) and/or causing nutrient lockout? Or is this a calcium deficiency? Is it a phosphorous deficiency since it was really looking fairly decent until flowering began? Is it something else entirely?

My plan is to use reverse osmosis water from the store now (sigh…) and add organic calmag and organic pH down. Please let me know if that is a terrible solution!

Humidity is 40-60%, but usually 40%, sometimes lower. Temp is almost always 78-84F, usually 81. Organic soil (Promix for herbs with “3 months feed” and myco and perlite, extra perlite, extra myco, vermiculite, worm castings).

I was using black molasses at first but realized that is really for flowering stage. I might start using that again, but I don’t know if that’s dangerous at the moment while I have no idea what’s happening.

Mars Hyrdo 150w TS1000 about 14" from canopy, did some very artless LST (feel free to advise me there too).

I also had some pollen sacs develop, and I removed those. I’m keeping really close watch for more.

This is my first grow, and I thought it was doing okay. It’s still doing okay, but obviously something is seriously wrong, if it’s developing sacs, has the chlorosis and necrosis, etc.

Photo spam below. I have included many photos of the WW, but I have also included for reference two AK-47 seedlings to see if anyone can spot signs of the same issues and thereby figure it out. I also have a photo of a basil plant.

If you start using RO or distilled water there is no need to adjust or check for PH as there isn’t anything in there like tap water.
When you add anything to that water you may want to know what that nutrient does to the PH. I always add a Tsp of epsom salt to my RO water and I know it doesn’t affect the PH enough to worry about it but if I was using my tap I might use citric acid to lower it as it’s above 8.
Some things will swing PH quite a bit but with enough buffers (oyster shell powder, crab meal, gypsum etc) in the soil and having a living dynamic soil it usually works things out to an equilibrium.

You may want to do a flush if you haven’t done one yet. This way using the liquid PH pen you can check run off as you flush so you can see which way it’s trending and know how much water you need to use to flush.
Getting PH to 6.5 or so with a range of 6.0-6.8 is goal during flush.

Looks like you have several issues going on here.
My first question is do you know what the soil PH is? If you don’t have a reliable soil meter you can do a slurry test.
Take a couple samples of soil from the pot a couple inches down or more along the side etc and put in a cup and add some RO water …not tap…And mix it up. Let it sit for 30 min or so and check using a PH pen for liquid (may want to strain off the solids first) and check reading.

Have you fed them anything like Neem meal or kelp meal or any thing besides adding molasses to water?

I see Pot-Ash-ium (K)

Phosphorus (P)

And this kinda looks like a PH issue I’ve seen before but not sure

Looks hungry even for some (N) too

If you can provide more details as to your water / PH and anything else that would help.
Here’s a chart to reference for temps/humidity ranges your seems too low of humidity for the temps in my opinion.

I’m sure others will offer up some ideas.


Looks like a combination of too much water and PH out of range.

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