First, you might just use a piece of black paper or a curtain to block the outside light. Keep your water changes going to export the waste products. Use distilled or RO
water to make saltwater and to top off. Its dissolved organic compounds from tap water or over feeding that the algae grows on. I suggest some snails, red and blue legged hermit crabs, but not that starfish. That type isn't easy to keep alive and I am not aware that they eat much hair algae. Reduce your feeding a bit as well.
Lifting a fish tank is a challenge for somebody with good balance, so don't feel bad.