If you have been to Japan or Europe, you may have seen moss balls - Aegagropila linnaei algae that grow into green velvety balls - and thought it would be nice to have.Don't do it. By caring about the environment and believing natural-is-always-better hype and thinking if Europe or Asia does it, it must be good, you could be releasing a devastating plague. Then put it in a sealed plastic bag and put it in a landfill. That's right, the plastic is safer for Gaia than zebra mussels. If you put them in an aquarium, you will need to boil it, drain it, and start all over.They look cool but your $5 investment could have long-term consequences so just avoid it.