How much filter media into a sump ??

[BugFriendlyGardener]

Ex reef sump to be used ......my sump holds nearly 40 gallons, suporting an 87 gallon tank. Divided into 5 sections. I can't find a formula for filter media. Input section, rough foam over bioballs; next two sections I intend to construct baskets to hold ceramic rings on either side of the overflow baffle. 4th section is just a narrow feed into the return pump so could be more foam or plastic pot scrubbers.

Any suggestions welcome, but HOW much media ie kg of ceramic rings. Or should I just fill it up !

 

[foxfish]

I wouldn't complicate things to much, some type of removable mechanical media in the first chamber, perhaps leave the next chamber for the heater, bio balls for the next two & pump in the last.