I need some straight talk from the experienced folks, I am getting some conflicting info from the LFS and older books. I would love to switch over to saltwater after years of freshwater tanks. I have a 90 gallon tall tank, It is 36" wide and 31" tall, somewhere around 18" front to back dimensions. I did the calculations and the actual water volume is around 86 gallons. I have two submersible heaters with external controls. I have a hang-on-back filter which circulates 400 gph, as well as a canister that pumps about 350 per hour. I have a full stand, hood, and a compact light 96W with an additional actinic bulb, and a flourescant light fixture that has two bulbs that I believe are 9625K. I have inexpensive access to a new protein skimmer with a powerhead that is rated for a 75 gallon tank. I see there is always live sand and some live rock for sale in my area (Chicagoland). I don't have any water treatment equipment, no RO or DI systems, I have been using tap water that I often age in a tub with dechlorinator for my freshwater tank. What equipment do I absolutely need to have to get a tank up and running? My end goal would be a tank with a handfull of fish, perhaps some crabs and/or shrimp, very simple at first. I want to start slow, I don't see myself going to a full reef tank, I don't have a ton of money or time outside of work and family, but what time I do have I spend cleaning tanks! I just want to get off the pot and at least get it started.