Fluval 2 gal, question about oxygen needs

I have a Fluval 2 gallon on my desk at work, heated. It's been going good for a few years, with a mostly happy Betta.

He died a while ago and I recently got four white cloud minnows and a shrimp (that kind of filters the water with jazz hands not claws, really cool!!) and I'm concerned about the oxygen level.

The Spec has in-house filtering, so nice and quiet, but no aeration that I know of. My Betta did fine because they 'breathe' from the surface but minnows and shrimp need the O2... Is the pump in the spec somehow enough? I have three live plants in it if that helps.

Thanks!

Edit: Singapore Shrimp, I finally found what subspecies!!