Mag def or ph issue?

selfmedicator462

Well-Known Member
i have never had a single problem with seedlings all the way up to flower. Usually my problems happen late in flower so this is new to me. Haven't wavered on my setup in the last 6 grows. Growing in promix hp with lots of perilite. Only feeding 100ppm of veg&bloom. Ph'd at 6.5. The leaves are getting twisted which leads me to believe it's a ph issue but the color looks like mag def. I'm using a Milwaukee meter that I picked up a grow ago. Calibrated it maybe a month ago. IMG_2096.JPG
 

Wetdog

Well-Known Member
Well, a pinch of epsom salts, top dressed, or a tsp dissolved in 1/2 gallon of water +/- will tell you in a few days if it's a mag issue or not.

No experience with ProMix per se, but I make my own mix using the same Co's peat moss and end up with pretty much the same thing. I always lime the mix. In fact, the lime is the second thing added with the peat moss being first. Nothing gets pHed from then on. 1cup/cf of mix, or, 1Tbl/gallon if top dressed. Takes a couple of weeks at least if top dressed, but will get there.

Both easy fixes, if either is the problem.

Wet
 

zubey91

Well-Known Member
there are some signs of Cal mag deficiency but i don't think thats it. what is your pH? it looks like lock out from PH
 

HydoDan

Well-Known Member
Tiger striped leaves.. magnesium deficiency.... I don't see any rusty spots... that would be calcium.. some plants require more mag than others...
Epsom salts...
 

selfmedicator462

Well-Known Member
I've grown this strain (alien OG) before and didn't have any issues. Checked my meter and it reads 0.05 low so not a huge issue. Not sure what I did. Maybe I zoned out mixing my nutes one day.
 

OldMedUser

Well-Known Member
Looks more like nute burn than lack of Mg to me. Maybe you did zone out mixing nutes. Not like I haven't done the same. :)

Nice small pot so I'd just give it a good flush and follow that with a 1/4 strength nute mix so they don't starve while you wait for the pot to dry out.

I grow with HP too and it has dolomitic lime in it that won't wash out with a flush and your nutes should have Mg and Ca in them tho a low dose of CalMag won't hurt.

:peace:
 

HydoDan

Well-Known Member
Looks more like nute burn than lack of Mg to me. Maybe you did zone out mixing nutes. Not like I haven't done the same. :)

Nice small pot so I'd just give it a good flush and follow that with a 1/4 strength nute mix so they don't starve while you wait for the pot to dry out.

I grow with HP too and it has dolomitic lime in it that won't wash out with a flush and your nutes should have Mg and Ca in them tho a low dose of CalMag won't hurt.

:peace:
Took a lot closer look and have to agree.. oops!
 

selfmedicator462

Well-Known Member
You guys were right. Overdosed! Might have to check my ppm meter. Checked her this morning and it was DEAD! Even after i flushed it. Live and learn i guess. Maybe the moral of this story is to do the work before you pack the bowl.
 

HydoDan

Well-Known Member
Sorry man that's too bad... sometimes too much is just too much.. you'll do better next time..
I remember getting dead plants as a Christmas present.. it sucks!
 

OldMedUser

Well-Known Member
Diagnosing leaf issues to figure out what's going on is about the hardest thing to do. Looking at those charts with sick leaves gives you clues but don't tell half the story. Those are all from older plants that have had time to eat all of a particular nute or the media has had time to get out of whack pH wise or there's too much of one nute locking out others.

In my grow bibles there are detailed descriptions of what to look for that can clue you in to the real problem. Each nutrient has a page of what to look for and the majority of them don't have pictures. Takes a bit of reading and some detective work but it's much better than just doing stuff that may make the problem worse.

With young plants I'd say most problems fall into 3 categories. Not enough nutes, to much nutes or pH is way out of whack. That's not counting diseases as being the source of the problem or bugs like fungus gnats you haven't noticed eating all the root hairs so your plant slowly starves the dies of thirst no matter how much you water it.

Sorry to hear of your loss SelfMedicator. Did you autopsy the roots just for future reference. Doubt there was anything going on there but never hurts to do a close examination as it adds to your innate feeling for reading your plant's needs that comes with hands-on experience.

:peace:
 

selfmedicator462

Well-Known Member
eh it happens i guess. Just hate to kill a plant when seeds are so damn expensive. Ive never had any early issues before. Usually I get some nute burn late in flower. Took me several grows to realize promix held nutes pretty good.
 

OldMedUser

Well-Known Member
I love my ProMix. Was on sale here recently and I'm all stocked up now. Got over 800L of it stacked up in my carport. I mix the HP with the Veg and Herb and the Potting soil ones for plants I will grow all the way thru in pots and hardly need to give them nutes in veg.

Got a little sulfur deficiency happening with my two Otto#1 hi-CBD plants but the other four are fine. They all got a dose of epsom salts last night so that should fix them up.

Here's what sulfur def looks like. Note the lack of green veins that you would have with Mg or N def. Even the veins go yellow with low S and the leaf stems go purple/red with some of that on the main stem too.

Sulfur01.jpg

:peace:
 

selfmedicator462

Well-Known Member
I think I finally figured out my problem. I'm still in the clone cabinet, in a solo cup and decided to just water it the other day. I used straight RO from my tank. The next day the top leaves started wrinkling. Same as before. I checked the PH......9.8 and I think it would have climbed higher if I left the meter in there longer! I use garden lime in my mix. I'm going to check my tap water tonight out of curiosity. I just replaced all my filters before my last grow. I grow in a 5 gal smart pot so it's not like I've ran a million gallons thru them. Not sure if that would affect ph or not anyhow.
 

OldMedUser

Well-Known Member
Do you mean the pH of your RO water is 9.8 or the run-off?

What kind of lime are you using? Hydrated lime is very alkaline and fast acting. That's what they use to lay out the lines between bases on a baseball diamond as it kills the grass under it. Dolomitic lime is what you want to keep the pH up and steady in soil grows. Even ground up fine it reacts slowly and supplies Ca and Mg in a good balance.

:peace:
 

selfmedicator462

Well-Known Member
The straight RO from the storage tank is that high. I use garden lime. It doesn't say dolomitic on the bag but I asked the place where I bought it and they said that's what it is. I've used it a few times now no problems. The only thing I've never done is use straight water from my tank. I've always either ph'd it or fed nutes.
 

OldMedUser

Well-Known Member
Something is wrong with your RO machine then. RO water should have no real pH of it's own as it should have next to zero minerals in it to generate a pH value. Do you check the ppm of your RO? Is your pH pen properly calibrated?

Some RO units come with attached mineralizer units to raise the pH for human consumption adding basically CalMag to the water and that allows it to be set for different pH levels. I grind a little pink Himalayan sea salt into my glass of water before I drink it as I have low blood pressure so go out of my way to increase my salt intake. Makes it taste better too.

Something is out of whack for sure.

I just went out and checked my big bag of lime and it's "Type N" High calcium hydrated lime. We spread some on the compost heaps and toss some in the outhouse to break down organic matter faster and that's the stuff not to use on the plants in other than very small doses. If yours doesn't say Dolomitic on the package I'd be suspicious. I have a box of Natural, Green Earth brand dolomitic lime I use for my plants. It's in BB sized granules that I will grind up in my mortar and pestle before adding to my soilless mix for my plants. The hydrated lime is very fine like white flour.

:peace:
 

selfmedicator462

Well-Known Member
I don't have a super expensive system. Value priced. 3 filters, 1 membrane and a final charcoal filter. I guess I've never checked the ph of RO before. Maybe it's been high the last 5 yrs. the ppm is usually below 100.
 
Top