Looking good. you should bend/train the untipped ones slowly over about a week almost parallel to the ground with pegs and string ,this will create more main shoots and you can do the same with them, much bigger harvest mate and you should have put this thread in the outdoor section so the boys...
Dont stop the nutes, with hydro you feed right up till harvest or the final weight will be affected. Looks like nute burn and 95 is far too hot, better cold temps than hot in flowering.
Yes it works very well. You need it at about 100,000 PPM for an hour ,it will cost you a lot more if you dont do it.
Also ive found that any spidermite killer with DICOFOL wipes them out for good, no sign of them after spraying on plants and around the room.
Its nute burn from the hot soil you used not suitable for growing dope. Also it is def of other nutes because too much of one can lock out another.
I would start again as would take a lot of time and tlc to bring it back, time wasted that could be spent raising new healthy plants.