Auto grow Variety Pack for Newbie

I love FF Ocean Forest! For 5 weeks everyone is so happy. My challenge is keeping them happy thereafter. My ppm’s checking the runoff’s were 500ppm. I’ve been so disappointed with the yield of my first grow, I’ve decided to feed it FF Grow/ Fish Shit/ Cal-Mag tea despite planting in Ocean Forest. PPM’s now at 1000 or so. Again, to increase yield, I bit the bullet and topped #6 & #7 today, in addition to maintaining the LST I began this week. I’m also slowly moving them under the light, which is on at 100%/18 inches since I have a 9 week old Bruce Banner Auto. It’s a long way from harvest unlike its brothers who were done at 9 weeks. Growing well has been a challenge after 5 completed girls. Small yields are discouraging.....but it beats buying weed and it has provided a magnificent obsession during COVID-19 isolation. Grow on!