Necrotic spots in DWC

[Tazard]

I have always had these. The more vigorous the growth the worse the spots. Leaves will turn light yellow and are still well attached. My tap water has chloramine and fluoride I am using a Boogie Blue Plus filter for chloramine and a RO filter for the fluoride. I use the full lineup shown except the Allen Extract.

[Deadhead91]

Hey there hazard the leaves look wet and the grow light is on so just from that it's mostly likely light damage from the leaves being wet, leaves should never be wet when the lights are on, it can wreak havoc on leaf health

[Tazard]

Only hesitation about Advanced is that right now nutes cost me $5per gallon per 4week veg/10week flower cycle. Advanced would be in the $20 per gallon range. I use 5 gallon tanks so $25 vs $100 per tank per grow.

[Deadhead91]

I think you should just root feed, I couldn't find anything about foliar feeding except to dilute the shit out of it before putting it on the leaves and really you should only use something that says foliar spray on it and research a lot about that product

[Tazard]

I followed the manufacturers recommended dilution rates for foliar feeding.

[Tazard]

Well I spent $200+ for enough Advanced Nutrients for about 2 grows. Give it a shot.

[Deadhead91]

Like at the bottom it says foliar spray, but root nutes aren't really formulated for the leaves to really digest then you got to wash the leaves and stuff and never get it on the buds

[Deadhead91]

Also try moving all that reflective stuff from underneath the plant farther away it will intesify the light and heat

[Tazard]

My leaves are 75F top, 76F bottom. Humidity is 60% on a controlled system verified by a hygrometer at each end of the tent. VPD=1.14 RH could be 65-70, might change that 🤔

[MadMike]

I don't think it is from misting the plants. I mist my plants during the lights on all the time without a problem. Plants get rained on and the sun comes blasting out right away all the time. It should be fine. In fact, misting during the cooler hours can make plants more prone to fungal diseases like powdery mildew. Powdery mildew is super rare in cannabis indoor grows so I mention it only as a horticultural reference.

The symptoms look like a phosphorus deficiency. Photos I have collected on nutrient problems match it pretty well. From my limited (but growing) experience, it's likely due to a pH issue. You don't mention your water pH, but between 5.5-6.0 is the target range. I've had deficiencies before from pH problems so I would check that first.

Looking at my photos again I see that it could be pH fluctuations as well. In a hydro system (I have no experience with them, I grow in coco which is similar but not the same at all) you may have some pH swings going on. pH - always my first check for problems.

First photo is phosphorous and second is pH swings.

[MadMike]

@DeadHead91
I should have read the post more clearly... I didn't see he was foliar feeding cal mag. ** need to read more closely **
From what I have read foliar feeding is a no no when the lights are on. But just plain water should be o.k.

[Deadhead91]

MadMike your good we're are here to help one another and learn and grow, grow, grow hehehe

[Tazard]

Spraying could only account for this grow and would not explain all the other harvested plants. So 100% that’s not my underlying problem.

[Green75]

Looks like a calmag deficiency.. Either use it or increase it.. No problems spray feeding with they lights on..in veg

[Tazard]

Great! As I said I don’t generally foilar Feed I was trying to determine if it was cal or mag without adding it to the reservoir. As stated previous grows had no spraying. I adjust pH to 5.6-5.8 and let it rise to6.3-6.5 and then drop it back down. So phosphorus is quite possible since in hydro it’s only available below about 6.2. So many possibilities but spraying should be eliminated since grows without spray have resulted in the same necrosis. Thanks for all the help and ideas. I will probably wait 2 weeks and see if I get spots on what are now new leaves with the Calmag.

Hey ic you’re also a test grower fo FB the little one is CC lol. I also do grows for Ripper seeds.

https://growdiaries.com/grower/tazard

[MadMike]

I suspected so. I have given my plants a dilute cal mag spray once in the past with no ill effects. It was a bit of an experiment.

[D.A.A.S.69]

Looks like needs cal-mag, like 75said above.

[Tazard]

Ok so I guess I run as is (with 4ml/gal Calmag and no HG Nitrogen Booster) and wait 2weeks.

[Tazard]

More pictures as well as complete documentation can be found here:

https://growdiaries.com/grower/tazard

[Tazard]

Thanks for all your help!!!