Bro good job raising the Rez they will definitely appreciate that. I would definitely get a tds meter, they are real cheap on eBay. As for your air pump the more air to the roots the better. You mentioned u went to Wally World they have that ecoplus aquarium two outlet air pump which works great in my seedling starter box I have two running for a 3gal tote to give you an idea. The more air the better. As for lighting DIY. You can get u 5-6 outlet power strip, go to Home Depot and get light socket that plug into the wall they're like $1.50 apiece and just screw the power strip to the side of your box for extra lighting