I'd like to try keeping a few shrimp in my 55g tetra tank. I don't want a "shrimp tank." I just want a few for the sake of variety, and if they eat a little bit of algae or excess food while they're in there, that sure wouldn't hurt. So, what kind would you recommend, and how many for a 55g? Also, what about CO2 and fertilizers and such -- they don't harm shrimp do they? Is there anything I need to avoid using?