Ah gotcha......no. I don't use ferts. I do an organic living soil and everything is mixed in when I mix up the soil. About the most I do now is compost teas or top dressings, but I haven't done any compost teas in a few months.
It does seem that i am getting a bit of N curl on the tips.....so seems my soil is a little N rich for the GDP. Every once in a while I will get strains that curl a touch. I am working on a couple different ratios for remixing my 2nd and subsequent runs so that I have options for strains I run constantly and learn their custom mixes.
I have a sativa, African Meltdown, and its a lighter feeding strain. Maybe GDP will be similar. A few times through and I can generally get a good feel for how a strain likes to act and what is my best mix for them.