Youngsters yellowing....

[TemptedSoul]

Sour Diesel
coir
Ebb&Flow flooded once a day
flora nova nutes
Fluorescent and 100watt mh
6 inch square pot
RO water -600ppm to start with-now 1000ppm
calmag 1/3 strength- about 1.5ml per gallon
res ph- 6.0 drifting down to 5.6 after 3 days then readjusted to 6.0

I think I may need to up the calmag and lower the ppm......any objections?

 

[touringfunkband]

What Coco are you using and was it bricked up or pretreated?

When was the last time you calibrated your ph pen?

 

[TemptedSoul]

Botanicare coir in a brick....been using it for years now-good stuff!

bluelab ph meter calibrated a month or so ago...I will recalibrate it again today!

 

[Hydro-Soil]

Stop using the cal/mag first...

Put 5ml in a gallon of water and check to see that cal/mag is the strength it's supposed to be. You might be overdosing them, even at 1.5ml/gallon. (edit: there was a rash of 300% strength bottles of that crap going around a while back)

100w mh and 1000ppm?? Please... drop those nutes down to around 750 for now... 850 if they look hungry in a week.

How wet are they when the next flood cycle comes on? How long is your flood cycle? They should be lightly moist when the flood comes back on... but not damp or dripping if you squeeze it.


editedit: Wait... ph going DOWN while topping off every day?? It should be going 'up'... Check your roots... they may have pests or (if they're soggy all the time) they might be drowning.
Stay Safe!

 

[SeaMaiden]

I think you need to increase Ca and Mg, but I really prefer using separate products for that. If you separate them and give them in separate feeds, then you can keep the total EC up. I would give Ca & Mg through foliar feeds to help bring them back. The Ca is going to be the most problematic for you, especially since you're seeing signs this early on. Get the Ca into the plant, in a big, big way.

If you want more specifics just let me know. I use Botanicare and have used Floranova Bloom, but not alone, to excellent results, as coached by DHF.

 

[TemptedSoul]

How does one foliar feed calcium?
Epsom Salts at 1ml per gallon foliar for the Mg.....right?


I thought it was almost impossible to overwater in non compacted coir.

 

[SeaMaiden]

I've never been able to overwater, but then I haven't set out to try. I figure flooding and leaving that for several hours is close enough to 'overwatering' to qualify.

You can foliar feed any liquid Ca product. I like BioLink 6% Ca. I use the Epsom at a volumetric measure of 1/4tsp/gal.

 

[TemptedSoul]

I was leaning more towards Mg.....what makes you think Ca?
What about these images says "Calcium Deficiency" to you...?
Is it the necrotic spots?

 

[SeaMaiden]

Yup, the necrosis, its appearance, regularity, and where it's observed.

The interveinal yellowing of lowers would suggest Mg-. Since there isn't much to go on in terms up upper, middle and lower sections of the plant, it can make teasing the two deficiencies apart a bit more difficult. But once I separated my Ca and Mg feeds I began to learn the difference between the appearances of the two, so I think it's a combination, but both can be corrected early on and easily, though Ca is decidedly more difficult to deal with during the grow as you can't correct the necrotic spots, whereas with Mg it'll green right back up once you correct the deficiency or imbalance.

Make sense?