Shrimps tank with lots of algae
There are several photos of one of my old tanks. As you can see it has lots of soft green algae. Algae as well as decayed plants are natural food for shrimps.
I grow algae in all my shrimps tanks. I just add extra plant fertilization and keep light working 24 hours for first several days. I found that soft green algae grow better in a lower pH. However, other algae will be good food for shrimps as well.