If I was doing one, and I almost did on my 15gal, I would set it up to run poly pads until I saw higher nutrients (for whatever your keeping-it will vary) then chemipure elite (if you want to lower phosphates). I used to use blue but I didn’t like it that much. I only “treat” carbon when I notice a haze-I run it for a day then take it out because my coral seem to hate when it’s in there. Tbh, other than bio spheres (if you need more surface area), there wouldn’t be much I would add and certainly not right away. If you do it right away you risk bottoming out nutrients and having dino/cyano bloom. Plus, the more dissolves organics, the more sponges/feathers/biodiversity you will have. I attached a pic of the two poly pads I use. Thin is for fine particulates after a water change and the thick is an every day filter. I run a top down filter so for you, you’d have to run thick and thin together because the thin won’t stand up to the water flow.
On a side note, I also use the thick in all of our freshwater tanks too.