Cal-mag? Help!

I really can't say exactly what it is but I'm experiencing almost the same thing and mine has just put in the UC 6 days ago my tap comes out at 50-60ppm so I just added .5/ml of cal-mag to see if that will help.
Do you have cal-mag in your system?

Whats your ph doing?
My plants always get ugly when transplanting into the uc.
I try to shoot for 150 ppm of cal-mag with RO. Now if Im using my tap at 200ppm I dont use cal-mag.
Hope that helps
BG

Ca- appears on upper leaves, necrotic spotting along leaf margins and veins, sometimes interveinally.

Mg- is on lowers, beginning with leaf margin yellowing that progresses to necrosis and leaf drop.

You also have reddened petioles, indicative of N-, P- or both. I'm leaning toward P-, especially if those leaves are mid-plant. I've got a couple of charts for you to use, the graphic chart does *not* depict Ca-.

I know it is the norm, but i do not find petiole coloration in cannabis to be indicative of a deficiency - many strains just naturally have colored petioles.

Good to see you seamaiden hope all is well.

Hello, Q9. :) 'Tis going alright out here. How about with yourself? I'm drawing a blank on where I would know you from, though.

I am beginning to wonder if, especially in the indoor arena, so many folks experience colored petioles that they think it's perfectly normal in every instance. I personally have only had a few strains that, when really running right, still have purple (not so much reddened) petioles. Those strains always also have stripes running down the main stalk. Stuff that has, say, some DJ BB strong in its genes, or like NL#5, that one had beautiful striping down the main stem that extended up the petioles, but only as striping and it was very bluish-purple. I spend a lot of time peering at everyone's plants and petioles, whose are green? Whose are red and why? Whose are purple, and why? How is it that this one guy's plant 'bled' red? What about the leaves? Should I learn how to dowse? Is that a dandelion, or something else? Why can't I eat those figs?

I also use other plants to gauge cannabis against in terms of figuring out what it's trying to tell me. For example, in many regards the hotter, and often much more difficult to cultivate, peppers are a very, very close cultivation corollary to cannabis. I'm not going to suggest that I'm anything resembling an expert, but I can read a lot of material in a short period of time and enjoy helping others and learning from others. Because I have helped others sort out issues and have seen things like those reddened/purpled petioles also go away, I feel that it can still be a good indicator, even if all by itself it's not something that makes a huge impact on quality or yield.