Nute burn? Ph burn?? Deficiency?!? HALP

[Cozy Amnesia]

Ok, I've been staring at this plant and pics on the net now for hours and I can't make up my mind.

Here are the facts: I'm growing in coco coir, feeding 9mL/g bloom only + a squirt of lemon juice making it a pH of around 6.0. Strain is an unknown haze I was told is Jack Herer and she's about 24 days into 12/12.

When I first noticed this issue, I thought "oh crap, salt buildup" because I wasn't letting the runoff actually, well, runoff. I flushed and, woah, the color of the run of was red . I flushed until the runoff was clear. But here's the thing...it didn't solve the problem.

Today I check the pH of the runoff and it was a little lower than what I fed it (can't tell for sure though, using a crappy indicator solution that goes as low as 6.0pH) telling me there is still salt buildup. It also looks a lot like a phosphorus deficiency - all the signs are there except slow bud growth (thankfully).

I'm just not sure what course of action I should take. I could lower the ph, maybe get something better than lemon juice for pH down. I could feed less nutes. I could feed more nutes if it's a phosphorus deficiency. Please help!

Ok, on to the pics:

What you can't really see is the curly up of the leaf tips. All of the leaf tips have necrocis and are turning a dull gray color. Some of the lower leaves are turning yellow. The leaves closest to the lights (cfls) just looking ugly as hell, as you can see. Also, most of the stems are a purple color - but it's been like that her whole life so who knows....

HALP!!!

 

[10k]

coco can get a pretty heavy salts buildup especially when not feeding to runoff like you mentioned.
Since you leeched the coco already, you really should feed it again to run-off to restore some nutrients to the coco for now...
but I'm wondering, you said you're feeding bloom only ?
Please tell us what kind of bloom only. For example If it's GH Flora series multi-part, why no micro?

 

[Cozy Amnesia]

Oh, ah GH Flora bloom. 9mL/g (per h3ad formula), which gives 0-60-90-41 N-P-K-Mg (in ppm). So it's a little low on the phosphorus, which makes me wonder if I should up it to about 12mL/g. But if the problem is nute burn, then that would be counter productive.

I think I need to just be more careful taking care of the runoff. That and buy a better pH test kit to see whats really going on. So far the problem is not too terrible but it will get a lot worse if I don't do something about it.

 

[Hazy Lady]

As said coco can build up salts and become acidic very quickly, if you are not using a PH pen, you should always water till a little run-off, 5 or 10% will be fine, alternate your feeds so every third feed is plain PH'd water, this should keep your coco stable and prevent salts. You can get a PH pen on Ebay for $15 that will die in 6 months to a year but it will be so much more accurate than test strips. You also need a Phos acid based PH down as lemon is too weak and unstable and would possibly be cheaper than lemon in the long run.

 

[Cozy Amnesia]

No micro? I thought the formula was 6:9, but I've never actually used coco. I do use the flora series though, and won't even leave out the micro near the end..

It is, but only until vegatative growth ends and flower growth begins, thats when you drop the N and micros.

So i've been feeding straight Bloom for only a week now, and already the leaves are looking kinda yellow??

 

[Hydro-Soil]

So i've been feeding straight Bloom for only a week now, and already the leaves are looking kinda yellow??

Has H3ad changed their formula??

**Quote**
In the coco, I am now using 6ml/gal micro and 9ml/gal bloom which gives the nute profile:
N 97
P 60
K 105
Mg 41
S 27
Ca 97

adding 1 g/gal epsom salts to the solution changes the numbers for mg and s to:
Mg 67
S 61
**Quote**

Correct me if I'm wrong but using straight bloom is going to destroy your plants.

GH also makes a product line called FloraNova With that line you do add only straight bloom. You're using 3 part though and will need the Micro throughout the grow.

Or did I misinterpret what you wrote?

Edit: I've looked again and can't find any reference to H3ad using bloom only. The formula I quoted is actually the general formula he started with. Flowering requires a stronger mix. There IS mention of using 'less' Micro but none of eliminating it completely. I'm definitely interested in anything you can link me to though.

 

[Hydro-Soil]

I'm not completely sure on the coco aspect, but it does seem like hes using the 3-part. The micro has ALL the Calcium, Iron, Zinc, Manganese, and a few other things..So I would probably flush then feed with bloom + micro.

 

[Cozy Amnesia]

Wow guys, thanks for the help! You guys really got me thinking and so I did some more research. It turns out my timing was a little off and I dropped the micro too soon. Also, I was thinking that I also needed more P and was thinking about uping the bloom to 12mL/g - that was correct as well. Here's a good post that explains everything:

Head formula merely uses 6/9 as the base for vedging and the first third or so of flowering. [...]it's 6/9 all the way until you're buds start to look like buds, then you up the bloom to 12 ml /gal and run 6/12 until the production of new flower material slows down, at which point you drop the micro altogether and run 12 to 9 ml of bloom until you are ready to start a nice 2+ week flush.

So why is it important to remove the micro completley at a certain point of the grow?
NItrogen leaves a bad taste in the buds if u don't flush it early enough

And at what point of the grow would u do this and how do u know when?
Usually about week 5 on most strains, according to head the indicating factor is when the plant stops producing calyxes

 

[mexilandrace]

how long does that strain flower?

it looks like a 10-12 weeker to me and according to what I read you shouldn't drop the micro at 5 weeks when that isn't even half way through flower.

 

[Hydro-Soil]

Wow guys, thanks for the help! You guys really got me thinking and so I did some more research. It turns out my timing was a little off and I dropped the micro too soon. Also, I was thinking that I also needed more P and was thinking about uping the bloom to 12mL/g - that was correct as well. Here's a good post that explains everything:

That's interesting. Never ran across anyone that nuted that way before.

So it's a taste thing, huh? Interesting. Maybe I'll try that one day but flushed FloraNova just tastes so nice now, I dunno. Glad you got a handle on it