Not really sure what the stem plants are, as they were part of some kind of "5 plants for 5 dollars" deal I got at one point.
The bushy one is hemianthus micranthemoides though.
The plants on the surface are lemna minor, salvinia minima, azolla caroliniana and some kind of water lettuce (any help?).
I find that the floating plants greatly reduce the presence of algae. I had a metric f***ton of algae until they took off and now there is none. They also create shady spots and launchpads for the shrimp. The rasbora maculata seem to like it as well. If it starts to take over, just scoop it out.