What's wrong with my girl?

[craftygirl]

This is a clone from a Coco Melon plant. She's been doing really well until the last few days. I am not sure what's wrong with her. I am growing her under 4 6400K T5 lights. (I grow all my girls under T5 lights and don't have issues) She was nice and healthy and dark green until about 4 days ago. Nothing on my end has changed, same water (Ph is adjusted down so soil is around 6.1-6.6 although it's usually closer to 6.1), same nutrients (fox farm trio for soil), same light schedule.

I'd be very grateful for any help.
Thanks

[Canuck147]

Adding any calcium/magnesium additive?

[craftygirl]

I haven't added any cal/mag. I never have added any cal/mag to any of my grows.

[DoctorJohnson]

That interveinal chlorosis betokens a magnesium deficiency fer shure fer shure. Easy to fix with Ca/Mg, but do it soon.

http://www.growweedeasy.com/magnesium-deficiency-cannabis

[RosettaStoned]

Looks like maybe a Potassium deficiency. Very limited experience with this plant is soil though. Definitely seak out other opinions

[DoctorJohnson]

Hmmm... maybe. I'm still thinking Mg. craftygirl: do you have soft water (i.e. low mineral water) or are you using RO water? That would make Mg more of a candidate.

Here's the troubleshooter: http://www.growweedeasy.com/cannabis-symptoms-pictures

[RosettaStoned]

My experience with Mg has been exclusively the bottom older growth if there is deficiency. Mg left untreated can burn the leaves but I don't think it would go that fast in soil. The burning tips plus the yellow margins is what makes me think Potassium. But like said, use the link doc provided.

[Sheesh]

I'm with Canuck and the good doctor, suspecting cal-mag deficient. Cal and mag uptake in soil from ph 6.5 and higher. I would increase ph to 6.5-6.7 range and consider adding cal-mag. Soil grows do best around 6.4 to 6.8 ph IME. Also make sure you're adjusting ph after adding all nutrients and additives. You may know this but just in case...

[DoctorJohnson]

And General Hydroponics says to add their CaMg supplement, CALiMAGic, to the water before anything else. Not sure if that's true for all supplements, but easy to do...

[Sheesh]

Good point. I've read that too and I think they said cal-mg, silica, hydrogard etc all go first. then start with flora micro before grow and bloom.

[Chefbjy]

Gh recommends armor si/ silica first then calmag. But no supplement I'm with mag or potassium. Calmag would help both.

[craftygirl]

Also make sure you're adjusting ph after adding all nutrients and additives. You may know this but just in case...

So far I only adjust the Ph in plain water, not the nutrient water.

I currently water (with Ph adjusted) on day 1, then nothing on day 2, check day three (and if needed) then do a nutrient feeding, then nothing on day 4, then check day 5 (and if needed) water (with Ph), then nothing day 6, then check day 7 (and if needed) do a nutrient feeding, and so on. Every so often I'll add another day of do nothing if they are still moist enough.

Should I always have the water adjusted with Ph? Even the nutrient water? I currently check the water run off when I water and feed and it's usually pretty even, on water only days, the run off is a little lower (around 6 or so) and on feeding days the run off is a little higher (around 6.5 or so).

[Canuck147]

Cannabis plants can only absorb nutrients in the pH range of 5.5 - 6.5

[craftygirl]

Campesino, Should I be checking the Ph of the nutrient Solution or just the run off after watering with the nutrient solution?

[Campesino]

Check the pH of the Nutrient Solution! This is the most important!!
Adjust the nutrient solution pH to fall within the acceptable range.
If you add water without nutrients, that should also be checked and adjusted before adding.

[Campesino]

Canuck147 The pH range depends on medium. I think that craftygirl is growing in soil and running pH too low. In soil plants should be fertigated with nutrient solution between 6.0 and 7.0. However, Ca is unavailable at the low end of that range. I have attached the GWE pH ranges for soil.
craftygirl your pH should fluctuate, moving up and down the range with successive fertigation events. This ensures that all nutrients wlll be available

[Canuck147]

What's fertigation?

[Campesino]

When fertilizers are applied with irrigation water

[Sheesh]

I like that word camp! Learn something new every day!

[DoctorJohnson]

........................