I don't know if pH perfect just mixes perfect or if it is supposed to stay perfect. Either way, nutrients need to be fresh to keep a pH balance, old nutrients that are supposed to be balanced will lose the effect. Technaflora keeps pH really well when fresh, so does the H&G, but if you are getting dusty nutes from a warehouse you won't get that benefit.
Your SFV is beautiful and frosty, but your leaves show signs of heavy stress from over feeding. Your cola's should be fatter than they are right now with that light, usually a large SFV cola can engulf a 22oz bottle of beer, I've got these results with less than 1300ppm and only 400w over head. Not bragging. But your hot sauce is too hot.
However, I don't see anymore light stress.