Heres the deal with the algae.
Your tanks new.So your going to have some algae outbreaks.It takes time for everything to settle in so that the tank can handle the excess nutrients.So the algae shows up.Its a pain,but it can be worked through.MAtter of fact,if you can post your readings for ammonia,nitrite,nitrate,PH,alkalinity,and calcium,along with what your feeding your fish and how much,we can you get through it lot quicker.
As for removing the sand,would you expect a wild reef to not have any sand?