to AA! The algae may be a bloom from all the cleaning. Believe it or not to clean isn't good in a tank.
Most likely the tank had algae before you owned it because of to much light and or overfeeding. The easiest thing to do would be only have the lights on for no more then six hrs a day and up your water changes till it clears. You could also buy a uv
sterilizer if you choose. Oh, and only feed the fish every other day. all those things together should clear it up in a week or so.
As to the Decorations. a water/bleach mix of 10 to 1. along with a good soak will fix those.(no driftwood) rinse well!
good luck hope this helps!