Aside from the forage minnows that went in last month these baby RES are the only fish in the pond.
I've been tossing a cup of catfish food every evening and the minnows have been cleaning it up.
I suppose I could catch a couple dozen and toss in the cage with the RES. Can't imagine it would hurt anything to try it anyway.

Right now the cage is sitting on the bottom of the pond, so whatever I toss in will settle where they can get to it.

I didn't even think about worms/nightcrawlers. Those are easy to come by and don't cost anything but the time to turn a few shovels full of dirt in my garden.

I wonder what the wife will say if she catches me squishing crawlers through her garlic press?