I would not do chamber(s).
A 10 gal is very small.
I would just put media be it lava rock, rings whatever (not really important) in mesh bags.
And as previously stated, because the sump is so small, submerged media would probably work best.
Trying to maintain a proper low water level as a wet dry, in such a small sump can be difficult.
And the benefits of wet dry compared to submerged are negligible.