Same old problem

[FreeVenice]

Ok so here is how it looks today. . .


lighter coloration. . . could it be the plant or is it still yellowing. . .

[foxysox]

Hi Venice,
I see the telltale striping of Mg def.
You had been foliar feeding before; now is the appropriate time to do so:
Dissolve 1/4 tsp of Epsom salts (Magnesium chloride) in 1 gal of lukewarm water and use that to gently foliar feed your plant.
pH strips come in all sorts of ranges and sensitivities... a broad-range one will tell you generally where you stand, then to be more specific, you'll want one that is within 1 pH unit up or down from the rough pH indicated on the first test.
Or... go to an aquarium supply store and get liquid indicator, which is the cat's ass.