I am in the process of setting up a new 40 gallon freshwater tank. I've had small fish tanks on and off for years, but this will be my first planted tank, and I'm getting lost in all of the literature about "must have" water amendments and filters and test kits and what-have-you. Is there any one thing that I can do to start getting everything balanced out while I'm learning? I don't have any fish yet, plants will be arriving in the next few days-Red Flame sword, a Madagascar Lace bulb, Potted Melon Sword, Amazon sword, Anachris, Moneywort, Hornwort, Cryptocoryne Wendii Bronze, and Ludwigia Repens. The tank has been sitting, filled, for a while as I've been researching/planning; I did a water test earlier tonight, and it said I've got high nitrites-I think that's what it said, anyway.