I haven't been doing this that long but I went from my first PF Tek to a small bulk grow (15L/16Q) within 6 or 7 months.
My bulk however had almost no strength. I tried 2G cracker dry & nothing....3G and still not even visuals. I would have expected something....anything....at 3G.
Here is the source:
TSW Syringe>BRF PF TEK>Spore Print from first & biggest fruit>Agar>Wheat Berry>2:1 coir/grain.
Results looked great and I had 20G dry from first & 25G from 2nd flush, but....low potency.
I still have the spore print left but is it even worth starting some agar from the same print or is it time for a new source?
I have a very accurate lab scale, didn't eat for 4 or 5 hours before, and no other medications to interfere.