help with cycling tank

[3450500]

My 120 tank was a complete loss Last wed i did a 75% water change hoping my live rock will come back. It has been so long since I have cycled a tank need a refresher course. I am starting to ge a light layer of green algee. Is this normal ? would apprecate any help going forward as to what I should do or exspect next. THANKS M.R.