Saltwater Aquarium Very GREEN. Need advice. Share with your Aquarium Smart Friends

I saw this aquarium on the local Craigslist and I'm interested. I'm a novice but I'm struck at all the green (algea?) in the water. Is it hair algae? Is it fixable? The seller says it has bloomed because he recently moved to his new house and disturbed the aquarium when he set it up.
Please give advice or share the video with your friends who know stuff about saltwater aquariums.
This tank comes with. QUOTE (from CL Ad) "It is fully cycled and stocked. it includes everything you need for it from the heater to nets to a full $50 PAIL OF INSTANT OCEAN SALT! its stocked with one sand sifting star, one cleaner shrimp, two peppermint shrimp, a hawkfish, maroon clown, six line wrasse, striped blenny, baby stars and a few crabs. One rock is covered in polyps"
Thx for the help.

[@TheCook12201982]

U need to get this stuff from fish store to take out the phosphates in the water and the will take care of the the white powder kind is my favorite

[@ExcelDriveVideo]

Great. Thx.

[@brilly21]

did u got it?

[@ExcelDriveVideo]

No, but it's still for sale. So I'm not out of it yet.

[@brilly21]

how much?

[@ExcelDriveVideo]

clarisse ramirez They were asking $300. WIth everything, live rock and fish.