Yellow leaves on Sativa not Indica

High there,

Two plants in 16 gallon pots outdoor NorCal. One Sativa other Indica. Buds are looking very beefy and oh so healthy on Sativa, but noticing yellowing fan leaves all around the plant. Indica right next to it, smaller buds but no yellowing. I trimmed back a little of the fan leaves about four weeks ago, but no more than 20 percent of the plants. Adding consistant NPK nutrients through the first three months and added bat quano, worm casing and kelp tea for the fourth month and now have moved to a phosphorous, potash guano solution for the last two applying every other watering (every fourth day). I have been adjusting the ph in the water before applying to the plant for the past month. Water going onto the soil has been at 6.5 consistantly on both. Tested the run off from below the pot yesterday and it read 5.8 or so.. PH problem? Too much nutrients (every fourth day) Something else? I have come this far and don't want to fuck it up.. Thx.

I have a sativa that is doing the same. Dropping more and more fans on a daily basis but she is still growing and doing well. I would say it's a characteristic of the grow and you will be fine but that's a guess.

View attachment 1773437

Fan leaves are used during flowering for their nutes. Green is the plants first pigment, yellow second, purple third but it usually just dies off after yellow. You are fine.