WHat to do about a neglected tank?

[beano1]

I went a way for 2 months, leaving my tank in the care of my parents. Who did basicly nothing. When i came back i was appalled at the tanks condition.My substrate has a thick brownish/purpleish/redish layer on it, my glass has stringy brown scum on it, and my water is about 6 inches low. I dont have any fish in it yet. What do i do to get it back to normal.

 

[tmkx3]

Just do a water change and scrap off the algea you can vaccum the sand but blooms are normal in a new tank

 

[Devilishturtles]

Lots of water changes will help alot. Vaccum the gunk off the gravel, sounds like cyanobacteria. With some time, it should return to normal.

 

[Hara]

I have merged your topics together, please only post the same question one time. Thank you.