I have 4 grand daddy purples all yellowing 20 gallon pods with fox soil and pearlite have feed them with cal mag and some Bloom still yellowing… and some spots not sure what is going on now PH is at 6.8
@Fifeforlife grate name buddy I actually come from an area called fife😀 have you checked the plants for bugs under the leaves also??
That was only next guess is some kind of bug, I have treated with neem oil & soap solution thru out there growth will look around today,
I live in Fife Lake Michigan
@Fifeforlife I live in fife Scotland
If you have a magnifying glass or a jewels loop will make things 10x easier as some pests can barely be seen by eye. Failing that I’d look next at a nitrogen/calcium deficiency bud but hold of and see.what some other think I maybe wrong lol
Lol five is a suburb of "greater Seattle "
pH 6.8 is a bit high.
Your soil looks wet.
Overwatering can cause yellowing like that. Lack of Nitrogen will do it too.
The spots look like calcium deficiency. Which will happen, especially in flower with rain/RO/distilled water.