I have a 20 gallon tank and I am wondering if I should put in any invertebrates like urchins and starfish. I have heard that starfish are not worth it and they are hard to take care of? What do you have to do extra for starfish. Also I am wondering about urchins and hermit crabs and other invertebrates. Which should I get? Also I want to know more about hermit crabs, urchins, starfish, and shrimp.
Thanks!!
Thanks!!