always
They don't have to sleep.
well starfish can sleep up to 12 hours like humans,but they dont have to sleep...
They sleep hidden beneath sand, keeping quiet.
yes they do they hide under the sand and stay very quiet
there are cusion starfish, reef starfish, spiny starfish and fire brick starfish in new zealand.
It is called toilet water.
Yes they can
Sure, starfish larvae are planktonic. Adult starfish are not.
Most starfish graze on film algae, and tend to go to where there are high quantities of algae. Chances are your tank has lights, and the algae will grow stronger closer to the light. The other reason is the starfish could be getting bullied by other tank mates, so it's just getting a break from the others. Look at your tank at night with a torch, the starfish should be down the bottom grazing while the other fish sleep.
Starfish Ancestors
they are starfish that is spiny
a starfish from the carribean?