Since I don't see any salt creep, I'm going to guess this is F/W (besides there is a S/W DIY section on here otherwise).
Is there a pre-filter (filter floss, poly-fil) and a drip plate?
You could fill the chamber with the pump and beside the pump with the orange bio-balls, then in the fist chamber put a mix of scrubbies and ceramic media with the rest of the orange bio-balls.
Now if we just knew if you have a big enough bio-load to support it all.
Dr Joe
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