Sand is great, just add your roottabs and you are good to go. It doesn't have a high CEC like eco-complete or flourite but if you keep up with fertilizing your substrate it really doesn't matter.
CEC stands for Cation Exchange Capacity - substrate with a high CEC means that it will be able to store cations (Mg-Ca-K) inside the crystal structure of the material. Zeolites/clays/activated carbon all have the ability to adsorb these cations making them desirable in these types of substrate. Alot of people will use cheapo kitty litter mixed in with their sand because it is composed of clay (good CEC). The roots can then access these stored elements when ferts are not readily available.
A high CEC substrate is good but it is not essential if you keep up with your fertilizer dosing. Roots will draw nutrients from the most readily available source, it is more difficult to draw the nutrients from the crystal structures so if given a choice they will draw from the root tab first.
