Hi, the water in my 2-year-old RES's tank gets completely green after exactly one week. I called Fluval to ask why this was happening and they said it wasn't the filter's fault -- it's algae, because the tank is in direct sunlight. I don't want to move him out of the sun because he loves it -- even with his UV-B lights on, he seems to be more into basking when it's in real sunlight as well. Is there anything I can do to keep the water from getting this way? Otherwise it's not dirty with droppings, food, etc. - the filter takes care of that. I have to clean the water weekly -- except for a couple of times in the last 6 months when I didn't need to change the water for over 3 weeks, which really confused me because otherwise everything was exactly the same (same water, same sunlight, etc.). Very confused! Thanks for any help.

