21 Gallon Rimless Reef

Going to try and keep this thread up as I build and progress the tank, am still in stages of acquiring all my needed equipment! Will post pics later tonight

But I need some opinions....



It will be a 21 gal tank with an overflow in the back corner.

I am going to add a 10 gal tank as a "sump"



Now the reason I used quotations on the word "sump" is because I do not know how I am going to run it and want to get some ideas



Should I just leave it as a bare sump with a baffle and then the return pump at the end where I can hide my skimmer, media, and heater?



Or should I make a middle section where I can place a light to grow cheato on a backwards lighting a schedule?



And lastly, should I use a bio filtration media, suck as making a box for bioballs or ceramic rings?



Need to figure out exactly what I will be doing with the "sump" then I can move on! All feedback is appreciated, as long as it is constructive criticism

Thanks

Matt