Filter media and refugium

[USMA36]

New 90 gallon mixed reef (eventually) tank about a week from adding water. I have a trigger 36 sump with 2 filter socks. I plan on running a reef octopus 150.00 and a refugium. After the refugium there is a small 2 layer compartment the top has a porous foam block. What should I put in the bottom compartment? When should I start the Refugium? What should I start it off with? I was thinking miracle mud, some rock rubble, and cheato. Is there a certain time this should be added? Will the copepods be able to make it past the foam filter section of my sump and up the returns?

 

[Oscar47f]

You can put whatever media you'd like in between the baffles some people use marine pure for extra filtration others leave the blocks you just don't wanna block it too much that it becomes clogged over time and restricts water flow, and the refugium can be set up just hold off on the algae since nutrients at first are low, some people wait some people don't... your idea on how to set up the refugium is good. And lastly the copepods should be able to make it through the sponge no problem