COCO COIR Leaf's discolored purple tips / General plant help

[Bowii]

Hello so This is my first plant I am growing and I personally believe its been going alright so far for a first grow, but recently for the past couple weeks or so I have noticed a purplish almost stem looking color appearing on the tips of some leaf's with a couple being a bit more noticeably affected as well as the tips of some fan leafs being a little bit curled. I have tried to read what the cause could be and the closest thing I felt like I could find was related to PH but I have been keeping that around 5.8-6 and was even more careful after reading that but It seems the issue is still persisting slightly. So with this I was wondering if anyone could help diagnose what the issue is and how to remedy it is my overall main concern as of right now. I have included some pictures and can add some more if it can help to figure out the problem if needed. If I could also get an overview of how people think my plant is generally looking or anything I could fix or do better would be greatly appreciated, thank you!!

[Allenpro]

From the pictures I would say your PH is off.
.What is the level when you water and after the nutrients are in and mixed?

[Bowii]

I have been keeping my PH around 6.0 between 5.8 but usually it is 6.0 within give or take .1 for range.

[Allotrope1000]

I have not personally experienced such, but would like to toss out the following.
- Have you checked the pH of your your runoff water? You should. Could be really off.
- pH of 5.6 to 5.8 getting towards low end of normal for a coco grow. Way below pH 6.5 to 7.0 for soil. We don't know what you are growing in.
- I use GH micronutrients on all my coco grows. Are yours getting micros?

[Bowii]

I am using coco to grow in, I am not sure what micronutrients are so id assume not, I have been giving fox farms nutrients every so often recently. I have not been paying close attention to run off because I don't have too much every time I water.

[Allotrope1000]

Hi, Bowii.
Micronutrients are trace elements essential to plant growth. Tiny amounts are required for proper plant health - copper, magnesium, boron, iron and others. These are necessary beyond the nitrogen, phosphorus and potassium in fertilizers.
Magnesium is the central element in the chlorophyll molecule (ligand) and can be absorbed by by improperly buffered coco coir
(cation absorption).

Here is what I would do.

Slightly overwater your plants until you have enough water to pH test it to identify or rule out pH issues. If out of range flush the plants with pH 6.0 or so water until the pH runoff tests in range.

If pH okay, check your Fox Farms nutrients to confirm they contain micronutrients (trace elements). If not add.

Add a cal/mag supplement to your fertilizer routine to counteract cation absorption from improperly buffered coco.

I follow the above and had never had a problem like yours. Check out the great grow info on the GWE site, too.

Let us know how this works. You are learning this just like reading, writing and arithmetic. We have all been there.