Consistent Cal? Deficiency

[4d-Rock]

Problem: Consistent deficiency which has been getting worse. I believe it is Calcium but even with adding 150-300 ppm CalMag it doesn't seem to help.

Medium/grow method: Pro-mix HP, peat based soil in 2 Gallon Smart pot

Feed: and supplements used: MegaCrop v2 and Calimagic. I have been using 1-2mL/L of CaliMagic every watering since I have seen spots in mid Veg, seemed to have gone away for a bit but spots have been coming back and getting worse. I have been using around 1g/L MC each feeding, and had been doing just plain pH'd water every second or third watering as I was seeing salt buildup and high ppms in runoff (I get about 500ml+ of runoff from 2.5L). Watering occurs every 24 hrs at this point, she's been a thirsty girl.

water source: Tap, sourced from lake. ~7.2pH/70ppm

Strain/age: White Widow Auto, Day 52

light used: 400W (200W Actual) Roleadro COB. Have tried to keep it around 12-16" but the plant outgrew my tent and I've had to Supercrop some branches to prevent them being super close. I have a HLG 135W QB288 3000K on the way though.

Climate: Day: 23-25C/55% RH, Night: 18C/60%

Additional info: Leaves on the lower half of the plant are overall more healthy, nice and flat, green, and only a few are showing minor spotting. Worst leaves are near the top

I have always had deficiencies in all my grows, not sure if the LED's cause it, or me underfeeding. But I usually increase until slight burnt tips, so I don't know if that's the issue.

Could also maybe need a PK booster? Or possibly the pH could be out in the soil, last nights pH in was 6.3, but runoff measured 6.6.

Thanks!

 

[MesaBoogie]

When I see my leaves curling in like that I usually back the lights off a bit. This looks more like a ph issue or P lockout imo.. Some smarter folks will be around soon enough that can give you a more experienced diagnosis. But in the meantime maybe do some research on the above mentioned issues because I don't think it's Ca/mg.

 

[4d-Rock]

When I see my leaves curling in like that I usually back the lights off a bit. This looks more like a ph issue or P lockout imo.. Some smarter folks will be around soon enough that can give you a more experienced diagnosis. But in the meantime maybe do some research on the above mentioned issues because I don't think it's Ca/mg.

Thanks for the advice. I’ve thought of that with the salt build up on the outside of the fabric pot. And I’ve suspected that in previous grows. I always try to water with a decent amount of runoff but I’ve never done any major flushes. Might be something to try out.

Also, I’d love to raise the lights but with my 4 1/2 ft tent it’s not possible. Like I said above, I supercropped but likely that’s not enough. I do have a quantum board coming which has a much thinner profile. I should be able to get another 6” of clearance when I get it next week.

 

[MesaBoogie]

I’ve thought of that with the salt build up on the outside of the fabric pot.

I've been looking the other way with that on my cloth pots lol.

 

[4d-Rock]

Hehe, ya I do for the most part too. White residue on the outside isn't the end of the world. But the plant suffering isn't ideal.

Last night I ended up doing a flush. 5L of water at a mild solution of 2ml CalMag & 2g Megacrop. Then a regular 2.5L watering with 2.5ml CalMag and 2.5g Megacrop. All ph'd to 6.1-6.3

I also just received a Apera PH60 pH meter to replace my cheap yellow meter. It turns out that the yellow meter is reading about .2-.3 pH low comparatively to the PH60. So I've likely been ph-ing my water/feed a bit on the high end, around 6.5-7.

Hopefully this sets things on the right path. I've checked in on it today and there isn't any drooping or other ill effects from the flush. Only time will tell if the deficiency or lockout issue is resolved. I'll still install the QB288 as soon as i get it to reduce the light intensity.

 

[4d-Rock]

Well, not sure what to say. After flush and back to mild nutrients I’ve done a few more waterings. Alternating feed and water with CaliMagic in each. All ph’d to about 6.2-6.3.
Here’s the top

Should they continue to get worse and slowly get better or what should I be doing at this point?

 

[4d-Rock]

Replaced the COB light with the HLG QB288 135W panel. Much more room in this alternate setup but the reduced heat output is bringing the tent temp down and RH up. Currently 21C/60-65%RH.

Unfortunately the White widow top leaves are still getting worse. Any one else have any suggestions?

 

[4d-Rock]

Still struggling and could really use some help guys.

Been doing a lot of reading and looking at deficiency pictures. Could this maybe be a Manganese deficiency?

It’s just not stopping and I’m starting to really worry that my most successful grow is spiraling into failure

Currently I am just trying my best to not do anything to drastic. Alternating between 300ppm CalMag on just water days and 150ppm CalMag and ~600ppm Megacrop on feed days. Always ph’d to 6.1-6.3

 

[MesaBoogie]

Damn, you're just getting no love in the infirmary. Seems to me 300 ppm is pretty high dose of calmag. I seem to recall reading somewhere too much Cal/mg can lock out P. I know your doing a lot of your own research so it's something else for you to check into maybe. What's the PH of your soil like ? Good luck man, hopefully someone comes around soon to help ya.

 

[4d-Rock]

Damn, you're just getting no love in the infirmary. Seems to me 300 ppm is pretty high dose of calmag. I seem to recall reading somewhere too much Cal/mg can lock out P. I know your doing a lot of your own research so it's something else for you to check into maybe. What's the PH of your soil like ? Good luck man, hopefully someone comes around soon to help ya.

Thanks. Ya it very well could be possible that heavy handed-ness in the Cal/Mg could have snowballed into some other issues. However, 300ppm is just the recommended dosage of 1ml/L of CaliMagic.

I don't have a soil probe, but I have tested runoff occasionally knowing that it isn't a really accurate representation of the soil pH. Has generally been within a few points of input water. A few weeks ago I noticed my cheap pH meter out of calibration and runoff was on the higher end. So I bough an Apera PH60, gave it a mild flush and have been keeping pH of inputs at 6.1-6.3 since.

It may have also been that I was making over-corrections, or even the wrong corrections which made things worse or at minimum hasn't fixed anything. Which is why I have been trying to keep it simple, make sure my inputs are within acceptable parameters, and hope for the best.