If the filter's pushing him down I'd suggest making a filter baffle for him, to slow the water flow so he doesn't get pushed around.
You can do that from a water bottle, or I think a small sponge in the filter would work too, but I'm not totally sure since I've never made one.
The only thing I'd put in there would be some red cherry shrimp or ghost shrimp. But:
1. He may decide to eat them, so they'd need hiding spots
2. They can be hard to keep. Some people manage others (me) have no luck with shrimp.
3. Ghost shrimp are sold as feeders, so are often handled roughly and not treated very well since they're expected to die, and are often pretty weak when you get them.
It could still be worth a shot, especially the red cherry shrimp, they'd look great on the dark gravel. :D