I posted earlier how I thought I was seeing nitrogen toxicity (deep green tips, curling tips) in my main-lined plants. After thinking about it, I think it may have something to do with my use of the so-called "
useless" formula.
Normally people run GH Flora's 3-2-1 at half strength. Useless runs it hotter, but I just noticed the nitrogen is disproportionately higher. The N is 12ml which is 0.8 of GH's recommended 15ml. The P-K are 6-3 which both are 0.6 of GH's recommended 10-5 mls.
That probably plays a part. I should probably reduce the N to 9ml which would be 0.6 of GH's recommended dosage, reduced proportionately to the P-K.
I just wanted to followup in case anyone else is using "useless" and sees nitrogen toxicity.