Day 39 of flowering, need help asap

[summitoker]

The strain is Dynamite(sweet pink grapefruit)
These plants are in a mix of about 70/30 coco fiber to potting soil, 3 gallon pots. 600 watts, high temp 80 degrees usually about 75.
Watering with the whole biobizz lineup, reverse osomosis water balanced to 6.2, about 10% runoff each time.
The yelow burnt looking tips, mainly on the lower leaves, came on real fast. I was quick to give each a flush of 3 gallons 1/4 strength bloom. Flushing did not help. It has been about 5 days since this started.
The leaves then started to become very brittle and now they are cupping up almost curling into a tube. The pic shows all the conditions.
There is only about 10 days till flushing was supposed to start. Please any advice would be appreciated.

 

[Pirate138]

Its normal for leaves to begin to yellow and lose green when the bud cycle is coming to an end. Shudnt you be flushing anyway?

 

[LokiBC]

Looks to me like over-fertilization. You say flushing didn't help? Do you mean the burnt looking leaves didn't improve, or more leaves are looking burnt? Once the damage has been done, that particular leaf isn't going to return to health, but if no new damage is occurring, you've done good.

Good luck.

 

[Aerokush101]

Nothing looks too wrong to me, I would continue what you are doing. If you assume you have 10 days left to flower, flush your plants using water only, let the plants use all the energy stored in the plant for the rest of the cycle. You should have a happy harvest. Just my opinion...

AK101

 

[HeadyPete]

I agree, flush now.....overfed slightly

 

[summitoker]

the flush didnt seem to stop more leaves from turning a nasty yellow brown on the tips. I have seen many plants start to yellow near harvest but this seems to be more of a nute burn.
The description of the strain says they can be pulled at 45 days but that is when i usually start to flush them then harvest between 55-60.
This is the first time i have ever had problems with this strain but also the first time playing with coco fiber.
The thing that has me worried most is the cupped leaves i have never seen that before?

 

[Aerokush101]

Whatever you do, unless you see damage to buds, do not harvest early. I have to be honest and say that my plants sometimes have a few problems when they are not dailed in exactly. But I have never experienced the plants to make me have to pull early, unless I was needed of funds. Continue your journey with your plants, pull the tops at 55, and the bottoms at 60. (My suggestion) See what happens then... PM me if you have more questions.

Some may not agree with how I do things so this is just my opinion.

AK101

 

[HeadyPete]

Don't stress, I've seen way worse plants give a good harvest, and your plant looks pretty damn good, not pristine like in a magazine, but pretty damn good!