What media to run in Remora surface skim box?

I just got Remora with surface skimming box. Maxijet 1200 is in the box now and it says that other compartment where skimmer return flows can house a sock with filtration media.

What media should I run in there? Another sock full of carbon? Phosban? Mix different ones together into a single sock? Put a buncha bio-balls in there? Something else?

Thanks.

 

Phosban is good, you dont need two socks of carbon IMO. Bioballs are a no go..Nitrate factory IMO.

 

What if I mixed Seachem Renew and Seachem De*Nitrate into a single sock and put it there?

Or Seachem Phosguard and Seachem De*Nitrate?

 

Should be fine, i mean its really what you want IMO.

 

Thanks for advice. Problem is I have no idea what I want, hence looking for some suggestions.