First Grow - Granddaddy Purple

Just got this plant on December 28th. All in all, I think I’m doing okay. Dealing with some yellow tips on some leaves, experimenting with water amounts, water ph, and the amount of light/ type of lamp I'm using. Until last night I was using a CFL, thinking that it was good enough for the small plant I had. Received some advice and decided to switch to my full LED light last night, hoping that will deliver good results over the coming days. I fucked up a few days ago with my Ph-ing of the water. I've been trying to fix that mistake by giving the plant clean water the last couple of days, then some fertilizer today in hopes of delivering nutrients. Thinking I'll finally chill out for the rest of the week and just let the plant do its thing.