U should just keep up the PWC
. Get some rowa phos to eliminate the phosphates. Use ro
water. Get some pro reef salt mix, preferably top marin. Clear out as much of that algae as possible before. U should have got just the live rock and sand, covered up let the tank so no light gets in (algae blooms won't happen without light) and leave it running for a few weeks. Good water and salt help because they are purer, so there are less bad elements for algae to thrive in, the algae cycle will be over and ur tank will be clean. damsels will become more aggressive and might kill something. Ur starfish is a hitch hiker from the sand or rock. If it is asterina it is a nuisance like aptasia. Take my advice for what it's worth, I was in ur situation.