how many kessil a360's would you recommend for a 12' x2'x2' mixed reef tank? Also is a octopus regal 220 sss enough of a protein skimmer for a 400 gal tank?
I have an 8' tank and I have 4 a360we's the width isn't so much of an issue because they do cover a great span. But you may run into something with the depth my tank is only 18" deep and keeping low light coral at the sand bed; they do well. Depending on how you scape your rock and placing more light requiring coral at the higher elevations may do the trick.