Ok, if you want to correct this, you can do this trick right now, then stop over-doing your plants... you are killing them with love.
Take them out of the 3 gallon pot, lightly shake and tap them until the 2gallon worth of soil that you put in there(and subsequently fucked up all to hell with your bro-science flushing, epsom salts etc) is off the root ball.
Properly repot them. DO NOT ADD ANY FANCY BULLSHIT to the new pot... just soil and the plant.
Once it's in there, water it with PH'ed water (test it before you put it in), anything between 6.5 - 7.5 is absolutely fine. Water it with about .5-.75g of water, water mostly in the root ball from the previous pot, sprinkle the last 25% or so around the outer edge where the new soil is(and no roots are yet)
Your soil has some buffer in it to keep it around 7 or less.
Btw this buffer is why your run off comes out super low... "run off" testing is for soiless growing, stop it.
Now, while you are waiting to make love to your plant again, take the same type of 3 gallon pot and put some soil in it and leave it outside in the sun away from anywhere it can get wet for about 2 days. After that, pick that pot up and feel how heavy it is(or light).... remember that feeling.
Now, 2-3 days later, maybe even 5 or 6, depending on how badly you raped your girl... lift the pot, try to support the plant stem with your hand to take the load of the plant foliage off the pot. (one hand on base of plant stem, 1 hand on bottom of pot) Pick it up and lift it up and down a few inches, slowly... figure out how heavy the pot is.
Is it lighter than the tester pot I told you to set up? Then water. If not, LET IT BE.
I've grown in promix a fair bit, my general rule of thumb with promix without any other amendments is approximately 1/4 the pot size of water.
So, in 1g, I'd only water 1/4 gallon. In a 3 gallon, I'd only water .75g
Pale color plants, many first time growers think it's nutrient deficiency... and technically it is, but it's because of lockout from overwatering.
Water your plants and look at them, in the first hour or so of lights on, after a watering you'll see the leaves kinda droop... but then they'll pray to the sun gods ... if they don't, you probably overwatered them...
Good luck, do less.