New to saltwater I Just got a used Biocube 32 gallon, what should I put in the filter media compartment and in what direction I have all original parts and carbon filter cartridge
Unless you have a specific need for any other media, I would run some basic filter floss for mechanical filtration (you can also use Poly-Fil, same stuff, sold at Walmart and craft stores to stuff pillows and is super cheap). A good granular activated carbon (GAC) and possibly some plastic bio media, largely just in case you need to quickly cycle a hospital tank (you typically want your rock and sand to be your main bio filter in reef tanks, not filter media).
Look at the intank media rack. They are designed so that the water flows down through it through your different compartments a little better than the stock rack does. in mine I hav floss on top, but I cut it a little smaller than the shelf so some of the holes are partially visible so air dosent get trapped under the floss, then i have a bag of Ceramic bioballs and in the bottom compartment i have a bag of Chemipure elite.
Using the Intank rack also allows you to have a decent refugium beside the media rack in chamber two. But for now mine is just full of rock rubble.
In chamber 1 i have my titanium heater and the Coralife skimmer. not sure how good the skimmer really works, but i do clean some goop out of it every week.