From what we are hearing & seeing, you just might be able to stock SMB. AaronM did great with them in a small pond in Phoenix AZ. He did also have a killer water filtration system as his pond was like 1/10 acre.

As Cody states in his recent article on smallies, the LMB eventually take over when they are present with smallies.

I have that same situation going on in my pond now and am getting ready to do a restocking of smallies while implementing a strict LMB slot limit removal plan.

I'm OK w/ restocking smallies every few years.

Like george says, the HSB are a no-brainer addition in my opinion.

Excerpt from Robert Crais' "The Monkey's Raincoat:"
"She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."