I changed a little over a third of the water in my goldfish tank about a 2 and a half weeks ago. Also cleaned gravel of fish waste and put in new charcoal filters and added water treatment to tank. For the last three days my clear/clean looking fish tank has become more green by the day. I've stopped using the lamp that covers the tank, although it has been on all winter ,I've used an algae remover tablet for last two days and I've put a dark sheet over a window that's by the fish tank. Any suggestions on how to get water clear again?

Thanks::confused:

It takes about a week or so for the algae to die and filter out after using an algae destroyer.
You may even have to dose the tank a second time.
Read the directions and see when you can add another dose.
Keep doing what you're doing with keeping the lighting low.
Good luck and happy fish keeping.:)