Calcium Or Manganese Def ?

[xinobyte]

The brown spots just showed up today on my top leaves after feeding 0.7 EC at 5.8ph.
My tips are burnt from trying to feed 1.0 EC last week, top leaves are yellow with burnt edges from what i assume is light burn (nothing i can do about it) and all my bottom & middle leaves are pretty much dead (turned yellow & felt off). The leaves closest to the sides are droopy because of the tent walls squeezing the plants from negative pressure.

Not much is making sense, most leaves look healthy yet i'll wake up tomorrow and dump 3-5 fan leaves per plant that turned yellow overnight. I brushed it off as "that's just what leaves do in flowering, they die" but now it's 2 weeks later and getting ridiculous. At this rate i won't have any leaves left by harvest.

Hydro Growers:
1. Are you growing from seed or clones? Seed
2. How old are your plants? 6/10 Weeks flowering
3. How tall are your plants? 3-4 ft
4. What type of hydro system are you using? Coco coir handwatered
5. What brand/type of nutrients are you using? Maxibloom
6. What is the Ph of your nutrient solution? 5.8-6.1
7. What is the PPM/EC of your tap water? 150ppm
8. What is the PPM/EC of your nutrient solution? 350ppm
9. What is the temperature of your nutrient solution? lukewarm
10. Does your PPM/EC show a rise or fall when you do your daily PPM check? Same as what i put in
11. Does your pH show a rise or fall when you do your daily check? Same as what i put in
12. Do you foliar feed or spray your plants with anything? No
13. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights") 400w HPS
14. How close are your lights to the plants? 1.5 ft - 2 ft
15. What size is your grow space in square feet? 3x3x6
16. What is the temperature and humidity in your grow space? 24c-25c ~ 30%-50% Day 18c-20c ~ 55%-65% Night
17. Have you noticed any insect activity in your grow space? No
18. How much experience do you have growing? 3 grows

 

[chemistry]

Look hungry to me, that's why your Manganese def has arrived. Do you run a good amount of waste to stop the salts building up in your medium?

 

[TerpyTyrone]

In your previous 2 grows did I keep the light @ the same distance this late into flowering?

 

[xinobyte]

I water until 25% runoff daily.
I've tried feeding more but, it only burnt my tips and didn't stop leaves from dying.
Maybe 1.0 EC wasn't enough ? What range do you suggest ?

 

[chemistry]

A plant that size could do 600ppm easy, and it's in heavy flower, they are greedy at this stage of flower. You wouldn't think 50 to a 100ppms would make much difference, but it does.

 

[xinobyte]

It's not PH issues that's for sure, i just ruled that out.
I'll try 1.2 EC tomorrow unless someone else wants to chime in.

 

[FatManatee]

If you have a calibrated EC meter that shows accurate readings, take a measurement of your run-off water, and make a slurry with 1 part soil 5 parts water and report back with the results.

Looking at the pictures only, there is nutrient burn, which means you are most likely locking out other nutrients. This problem will not be fixed by adding more nutrients, quite the opposite it will get worse. Flush your medium with plain water, from next watering onward start feeding nutrients at half a strength from what you are doing now.

 

[FatManatee]

Here's a table of the EC values you should have, when soil is mixed @ 1:2 and 1:5 ratios with water.

 

[Enforcer]

I water until 25% runoff daily.
I've tried feeding more but, it only burnt my tips and didn't stop leaves from dying.
Maybe 1.0 EC wasn't enough ? What range do you suggest ?

Your plants are in full bloom and sucking up a lot of water. I bet they are drying out the coco too much between your daily irrigations. This results in some of the salts drying on the coco. When you water again, you rehydrate those salts causing the burn. So even though you are feeding low EC, you get burn.

To fix the issue, I recommend you mix up a batch of your nutes at about 1.0EC. Flush your plants very well using this solution. This will reset the coco to the EC you want. Then begin 2 or better yet 3 irrigations a day. After a few days of multiple daily irrigations, reevaluate the plants condition and up the EC if needed.

Just so you know I’m not feeding you BS, these plants (3 different strains) are in week 7. They have been auto fed 4x a day since flip. 3x a day in veg. Currently feeding a 1.3EC. You are on the right track with daily feedings. But when they get big, it needs to be increased.

 

[chemistry]

Your plants are in full bloom and sucking up a lot of water. I bet they are drying out the coco too much between your daily irrigations. This results in some of the salts drying on the coco. When you water again, you rehydrate those salts causing the burn. So even though you are feeding low EC, you get burn.

To fix the issue, I recommend you mix up a batch of your nutes at about 1.0EC. Flush your plants very well using this solution. This will reset the coco to the EC you want. Then begin 2 or better yet 3 irrigations a day. After a few days of multiple daily irrigations, reevaluate the plants condition and up the EC if needed.

Just so you know I’m not feeding you BS, these plants (3 different strains) are in week 7. They have been auto fed 4x a day since flip. 3x a day in veg. Currently feeding a 1.3EC. You are on the right track with daily feedings. But when they get big, it needs to be increased.

Looking good E, some nice frost.

 

[Enforcer]

Looking good E, some nice frost.

Thanks Chem, one more week then flush. I can’t wait :)

 

[chemistry]

Stick some pix up before you chop, would like to see the plants fully grown at 8 weeks.

 

[xinobyte]

Here's a table of the EC values you should have, when soil is mixed @ 1:2 and 1:5 ratios with water.

Ok, i've done a slurry test and the result is 0.27 EC at 1:5 ratio. Seems fine to me.
My medium is still wet from yesterday but I'll try feeding 1.0 EC 3x a day nonetheless.
Good thing tap is free because that's 9 gallons a day.

 

[chemistry]

Ok, i've done a slurry test and the result is 0.27 EC at 1:5 ratio. Seems fine to me.
My medium is still wet from yesterday but I'll try feeding 1.0 EC 3x a day nonetheless.
Good thing tap is free because that's 9 gallons a day.

Don't let them dry out, keep feeding a few times a day or salts build up, and then you'll be lucky to work out whats going on with your plants.

 

[Enforcer]

Ok, i've done a slurry test and the result is 0.27 EC at 1:5 ratio. Seems fine to me.
My medium is still wet from yesterday but I'll try feeding 1.0 EC 3x a day nonetheless.
Good thing tap is free because that's 9 gallons a day.

Yeah, you’ll want to have a good source of water that’s not buying it from the store. Coco is basically hydro, although some people mistakenly treat it like soil. Watering every few days like soil will lead to issues in late veg and flower. A good rule for coco is:

If it’s wet...water it.
If it’s damp...water it.
If it’s dry...you fukt up.

The idea is to displace any of the old stale nutrient solution, with fresh aerated solution. That’s why run off is so important. Multiple and consistent irrigations a day lead to explosive growth in coco.

 

[Enforcer]

Also, I just looked at your pics again and I noticed your using fabric pots. They’re great, I use them as well. But they will dry out faster than plastic pots. Requiring you to water more frequently to avoid problems.

 

[xinobyte]

When posting this thread, I said no pests were present but i just noticed white creepy crawlies on my top soil.

They're too fast to take a good picture of but they're white with 6 legs (i think) and 2 antennas.

View attachment 1.mp4

 

[Homesteader]

Looks like thrips but you would probably see smaller larvae on the plant in the creases and folds of the leaves and stems. Look for damage on the leaf low on the plant. Quite common in soil. Im sure I have a few hanging out. They move to the soil when they are ready to pupate as the become adults. I've seen a few nasty dark ones that were well over an inch long as adults.

 

[xinobyte]

Looks like thrips but you would probably see smaller larvae on the plant in the creases and folds of the leaves and stems.

I haven't found any insect on my leaves, stems or damage anywhere.
I did find the reason i have pests tho, my girlfriend bought some stupid flowers at the grocery store a week ago and surprise surprise, when i picked a handful of dirt it was full of tiny black bugs with antenna... Unreal...

 

[Homesteader]

They literally are everywhere that there is soil. Really common in greenhouse production. I would assume they are on the plant though if you look close enough. The young ones are very small, like the size of a grain of salt.