VitaGrow is the cheapest out there and works as good as any of the big name brands. With your size resevoir you can do a whole grow for $25. It's three part and you won't need any additives because the three parts SuperFastgrow "calcium nitrate 17-0-0", SuperMicro "micronutrients 4-14-24", and GiantBloom "monopotassium phosphate 0-51-34" has everything the plant needs. You use 1/2 teaspoon of grow and micro per gallon for vegetative stage and add 1/2 teaspoon of bloom per gallon for flowering stage. As simple as it gets. You can buy a 1 pound box of micro and bloom for $9.95, the grow is $5.95. They have bigger boxes at a discount.
It's as "set it and forget it" as you're going to get. You won't be chasing ph levels like so many of the big name brands. Mix your solution, set the ph at 5.8, and forget about it. The ph will be low after mixing the solution so you'll need to up the ph. Just get a bottle of Red Devil or Rooto lye, mix 1 tablespoon with a gallon of water and you just made a gallon of ph up. A bottle of lye is $5.00 and contains 16 oz of lye so you can make a lot. Beats paying $10 a quart. I've been using it for over a year in hydro without any effects other than saving a bunch of money.
Another thing I should mention is that before I started using Vitagrow I tried all kinds of different products, Botanicare, General Hydroponics, Dutch Master and a couple of other ones. None of them did any better than VitaGrow. The only thing they did better was empty my wallet.
