Dangit, cant give any more rep to you bro
If ur plants are still suffering, you might wanna try some superthrive along with the correct nutes.
I ordered a pint myself a few days ago for 30 bucks with free shipping. Its prolly gonna last forever.
your plants are very yellow, did they get burned from the light? OR looks like not enough N in your setup. You could douche them with some Fish Emulsion 5-1-1, would stop thier suffering fast, BUT the damage done can't be fixed.
Good call on getting a pH tester, it might be a pH problem.
Some nutrients can only be absorbed at certain acceptable pH levels (differs between soil/soil-less/hydro).
Once your pH goes out of that range, your plants will stop absorbing certain minerals, even if they're in the growing medium. Soon after, your plants will look like they have a nutrient def.