You can download the catalog here.
Basically, it is a very small tank with IOS (internal overflow system), so no sump. IMO, it is too small to house a skimmer (not unless you're talking about those that run with an air pump and wooden diffuser), and for such a small tank, running a fan will do. The stock lights are all white LEDs, so I have purchased separately, the marine version of the same type of lights. It is slightly bluish, but definitely worth the swap if you're keeping marine.
IQ5 would be launched prolly end of this year or early next year, according to Dymax's representative.