Yellow leaves and some burnt tips on my girls, 49 days in flower

[Slice107]

Noticed when the lights came on this evening that two of my Blueberry Trainwreck's leaves (nearly all) yellowed over night and have some burnt tips and leaves. They were thirsty when I watered and fed them, but this is the first time I have seen this. The rest of the BBTs look fine and these are the two directly under the 1000w HPS. The tips of the leaves are more yellow than the base, which still has some green to it. Recently applied some dolomite lime to the tops of the soil to help maintain PH, not sure if that is what caused this. Appreciate any help I can get.

Medium: roots organic
Fertilizer: Maxsea Veg/Bloom 50/50 mix, CalMag, Hydroguard, Molasses, Orca, Floralicious.....all at recommended levels on label
Water PH: 6.7-6.8 each watering (runoff is PH of 8, thats why I added the lime to balance it out)
Temp: 76-80
Humidity: 35-40


Not able to post photos, not sure why, but I will get them up asap

 

[Slice107]

Here are the pics

 

[Antics]

That's a really high runoff PH. If you're giving it water PHed to 6.7-6.8, and the runoff comes out at 8, the PH in the soil will actually be a little higher than 8.

Is your PH meter accurate? You can check it with distilled white vinegar, which will read 2.4.

When did you add the lime, and when did this problem start?

What is the runoff PH now?

I'm thinking we either have a PH issue, or a Phosphorous deficiency due to lockout.

 

[Slice107]

Turns out it was my ph meter that was the problem. Bought some ph 7 calibration fluid and the meter said it was at 11. Wow, couldn't believe it was that far off. So I've been going in the wrong direction this whole time. Tested the ph of the runoff after calibrating the meter and it was 5.7. So I will start working it back up to 6.5-6.7

 

[Antics]

Turns out it was my ph meter that was the problem. Bought some ph 7 calibration fluid and the meter said it was at 11. Wow, couldn't believe it was that far off. So I've been going in the wrong direction this whole time. Tested the ph of the runoff after calibrating the meter and it was 5.7. So I will start working it back up to 6.5-6.7

That's the same exact thing that just happened to me. It sucks, but it's also nice knowing it's not something we did. After I fixed my PH, I saw AMAZING results in 4 days. My plant was in Veg at the time, but I'm sure you'll see similar results, and not sacrifice too much yield.

Good job catching the problem early though!