hahaha yeaaah that's why she's getting a lot of algae. After all the sun isn't out all day. When you have live plants you'd leave the lights on 8 to 10 hours. Without probably less is better since you wouldn't have plants to help combat the algae growth.
To help with the algae she could do a few days of black out. But if it's blue green algae that's different and not really an algae. I've had that stuff. Not fun.