This is a very solid explanation.
To read through these comments and see some of the recommendations and I just can’t help but 
Super soil is suppose to be water only because it is packed with everything it needs long term, BUT ONLY if u have a healthy soil with healthy active microbes which at a pH of 8, def not the case
Op already stated pH is too high at 8 which as we know about nutrient availability, that plant ain’t getting the essentials nutrients and to the untrained eye a yellow plant just appears hungry and most think just throw food at it. But when the roots are sitting in a medium that’s 8 that’s like trying to feed a human with a sowed shut mouth.
To hear comments saying maybe ur soil is tapped out and needs more food makes zero sense knowing the pH is locking out AND it’s a super soil
The plant is bushy but in a 7 gallon is not a concern of oversized, basic requirements suggest 1 gallon per 1 ft of height for minimum substrate needed (ever notice autos recommended is 3 gallon and rarely get over 3 ft tall?)and seeing the soil pulled out the pot and not being obliterated by roots should easily confirm that suggestion, there is def still plenty of room that an up pot wasn’t necessary like was suggested several times
Bottom line the plants arent gonna get better without getting to the source of the problem with actual problem solving solutions
Problem: pH is way to high
Solution: flush the fuck out of the soil to get what’s driving it up blasted out of there, not dump a couple gallons, take ur garden hose with a shower nozzle and blast that shit till the water starts running off clear. Let sit for 15 min then do it again
Problem: plants haven’t been able to uptake any nutrients for weeks
Solution: brewing an aact with primarily worm castings, alfalfa, kelp,a pinch of gypsum(helps pH buffer) and if possible some blended aloe leaves and immediately root drench about an hour after the flush and throwing some of it in a spray bottle and foliar spray as well. This is gonna get immediate soluable available nutrition in the root zone in a pH adjusted soil after it’s problem has been blasted out and doing a foliar with it is gonna get those plants immediately fed through their leaves till we can get your root zone sorted out
Problem: Microbe populations aren’t healthy
Solution: getting the pH in an acceptable range they can thrive and restore with innoculants such as recharge, Dr earth, down to earth, etc OR my recommendation of the AACT
type in my username and go look at any of my grows, I don’t have deficiencies, I don’t have lockouts and I’ve even had months at a time I didn’t feed anything, the Fem autoflower breeding run I did, I didn’t feed anything once for a wall to wall room of 55 of em. I understand these plants needs, nutrition requirements and above all soil health to keep a happy and charged soil. So I really hope ur not taking my advice with a grain of salt
Bottom line the pH range u need to have ur soil hitting is 6.2-6.5, till u can get it there ur not gonna get those on the right path to get ur soil and it’s microbes functioning properly
Here the veg tea recipe I use
And there’s a link to my soil building thread that I still use to this day for cost efficiency and a better mix than most bagged shit and I’ve never had to pH a damn thing with it