So I've been growing 3 plants that I thought were autos but now I'm convinced they are photos so I switched the lights to 18-6 and one is looking kinda yellow so I think she needs nutrients. Should I switch the lights to 12-12 because they have all been veging for atleast 6 weeks
It’s not inconceivable for a mix up of photo and autos. ILGM sells both for white widow.
If it’s been 7+ weeks, flip it to 12/12 and don’t look back.
Again, if you wanna play it safe, give it a week but after that, flip it