Necrosis/Dying leaves

[stoneRR]

Sup blades? Ok, first off, I don't have a pH meter so I cannot accurately gauge and measure pH. I will hopefully be acquiring some pH test strips today. With that said, I have suspected a low pH for my whole grow due to the peat moss making the soil more acidic.

I have adjusted my pH with sodium bicarbonate twice, using a teaspoon per half gallon. I suspected Mg was being locked out of the soil and causing some light green shading on the edges of the leaves, followed by some necrosis and eventually dying/brown leaves. Last night I foliar fed with a teaspoon of Mg.

I'm also not very sure if it is a Mg def., although that's what I first thought. However, I may be wrong, but that's why I am asking for help. This assumption was based off of a deficiency guide.


My setup

Soil - Scott's Top Soil, peat moss, perilite, vermiculite
Temps - 83 - 85 off / 85 - 89 on
pH - N/A - tap water pH is 6.5 - 7
Lights - 18/6, 200 watts CFLs
Age - About a month old
Ferts - None as of yet (want to get the probs cleared up before I add more chems to the soil)


You can't really see to well, but if you look close you'll notice a lighter shade of green on the outside edges of the leaves and darker on the inside. Notice the leaf tip on the far right starting to turn brown


And then this is what is happening to them



Would it be alright to trim off that big fan leaf? It's blocking a couple potential budsites and I think it would greatly benefit, but I don't wanna stress her too much




Diagnosis? Any suggestions as for the trimming?

peace

[Nada420]

Looks like a micro nute deficiency

Mg i think

give her a tsp of molasses or a bit of maxi crop and see how she likes it

[Nada420]

sorry i really didnt read your post

Yeah looks like MG

You really need a Ph test man

It may be a screwed up PH causing nute lockout


I would flush her with pH balanced water then do what i said above...

[stoneRR]

Ok, would I be able to judge the pH enough using a pool pH tester? It's the kind of thing you pour the water into and add a couple drops of phenol red and it changes colors ranging from red (base) or yellow (acid). It ranges from like 6.2 - 8.something but based on the color you can make a somewhat accurate guess as to what pH really is.

What are your thoughts on that?

[Nada420]

Originally Posted by stoneRR

Ok, would I be able to judge the pH enough using a pool pH tester? It's the kind of thing you pour the water into and add a couple drops of phenol red and it changes colors ranging from red (base) or yellow (acid). It ranges from like 6.2 - 8.something but based on the color you can make a somewhat accurate guess as to what pH really is.

What are your thoughts on that?

yeah man this will work

you can also check your soil runoff like this
would get a nice pH tester for later use tho

Heat might also be a prob