Gotta problem stumpin me

[Hushpuppy]

Hey guys(Gals included); I have been noticing a problem starting on my latest bunch of plants that are in both tents. the problem is occuring in the older leaves but across the plants from bottom to top and is now progressing to the younger leaves. It is happening simultaneously in 2 different strains that are residing in 3 different tents. Both sets of plants are getting the same nutrients in coco/hydro. PH drifts from initial setting of 6.2 down to 5.0 and sometimes down to 4.5 before I check it and readjust it.

The issue initially started in the lower leaves of both sets of plants and appeared to be tiny round necrotic spots as if they were being bitten by juice sucking bugs. But I have not seen any sign of bugs other than fungus gnats that I have been keeping under control pretty well (although not erradicated because of the easy access that they have to my grow space). At this point I am very certain that the problem isn't bug related as I have checked multiple plants with magnifying glass and found no signs of critters.

The initial onset starts out as tiny spots but later the leaves start to twist and discolor a bit. I am certain this is either a deficiency or related to the PH swing that I have been fighting with.

I have been using these same nutes/water (and same setup) for almost a year with no problems till now (AN Jungle Juice with Technaflora's Magical, typically 10ml per 15liters of water with every water change or addition)

I would appreciate any ideas as I am a bit stumped at this point.

 

[pcduck]

Pics would help

But I would guess pH on the crinkling and are the spots white?

If white could be the onset of PM.

But really hare to tell without pics.

 

[Budders Keeper]

I vote ph swing. I've noticed twisty leaves when my ph starts swinging(res change time for me). I grow in rocks, not coco. When I did grow in coco(massproducercocobuckets) I had less problem with ph than with rocks, or rockwool. Maybe there is an underlying problem causing swing? If me, I would focus on narrowing the swing, 4.5-6.2 is a pretty big swing even in coco.

Those are my thoughts. I'm sure you'll get lots of help with as much as you contribute to everyone elses grows.

GL

 

[Growdude]

If your PH is dropping that much in week? then I suspect there are some elements that are building up in the medium. As you know some strains use less than others but these leftover elements build up to a possibly toxic level.

Now this can be true if you see no change in ppm but PH is dropping.

If this is true flush out your medium some and go easy on nutes a bit.

 

[BackWoodsDrifter]

I be readin this here thread title and come rushin in to see ifin a brawl broke out firside

BWD

 

[Hushpuppy]

Hey, thanks guys. I didn't realize the pic didn't attach itself as I was in a bit of a hurry this morning when I posted it. I'll try again to attach the pic:

Hey Growdude that sounds like a plausable idea as the ppm doesn't drop much during the PH swings. I think I may have the solution for the PH swinging so wildly. My Bro has been having the same problem for a while now and we determined that we had far more (chowhounds) pulling on the resevoirs than the resevoirs had the capacity to supply without causing rapid chemical change that in turn causes PH to change. He changed his setup and added a 30gal rez to the existing 12gal rez that feeds 8 plants. After setting this up, he found that his PH didn't move more than .3 over a 5day period. He has been testing this setup for 2 weeks now and has noticed a big difference in the PH drifting very little and the plants are very lush. I am in the process of increasing the size of my rez from 90liters to 180 liters (or about 50 gallons) and see if this corrects my problem.

 

[gourmet]

Twisted leaves on old growth could be a boron problem. But the spots may magnesium and/or potassium. I am going by the charts and pictures of nutrient problems so others more experienced are better to weigh in.