Two days ago I noticed some of the older leaf tips starting to turn brown on the rim and yellow-ish around the middle of the leaves. Yesterday I noticed that some of the newer leaves are starting to do it and today I noticed the very newest growth is starting to show signs of turning yellow-ish.
Here's a pic of the biggest leaf damage:
Here are the latest stats from my most current readings:
pH: 6.1 on 1/15/17, lowered to 5.3 today (1/16/17)
PPM: 662
Nutrients: General Hydroponics Flora Series (Micro, Gro, and Bloom)
Additives: Rapid Start root enhancer, Floraliscious Plus (first used 2 days ago), Armor Si (first used 2 days ago)
I'm leaning towards a Potassium deficiency. My pH was consistently at or above 6.1 for a full week (since my last water change a week ago) and from what I read, if the pH doesn't get to 5.8 or below at least some of the time, then Potassium is locked out. Am I correct in thinking this?
Assuming I'm correct, I lowered the pH just now to 5.3 to give it lots of time to creep up above 5.8 again. Is this the best way to address the problem or does anyone else have any other suggestions?
I'm open to any and all feedback and thanks for taking the time to read this! Cheers peeps!