Hi there goodleaf, that's magnesium deficiency , you'll need to add calmag for that. I'm seeing the start of P&K deficiency. Unfortunately in flower plants need more PK and calmag, it's a good idea to have some on hand just in case. If you dont do anything the plant wont die but it will get worse, you'll see colorful splotches on the leafs and the final product will be a bit less strong and smaller. Hope this helps ! 🚀