Hi Ricky - the algae is looking suspiciously like Hair Algae, which is a nuisance algae and you definitely don't want to propagate that in your tank! So, make sure you're doing regular water changes to help keep your
nitrate and
phosphate levels reduced. Make sure your
skimmer is producing nice scum. Cut back your lights to a minimum as well - this will help out. Are you feeding anything at the moment?
The little starfish is an Asterina starfish, which is a nice little detrivore/herbivore to have in your tank. They can multiply prolifically, but usually don't pose a problem. They often have uneven leg length, and even different number of legs! Don't worry about them, unless they start taking over your tank.
