Algae isn't necessarily bad if it's not killing your plants or obscuring the glass. It's a very natural thing on rocks and such.
Algae grows for several reasons- excess nutrients(fish food, fish poo, dieing plants etc), excess light.
Fast growing live plants will suck up the extra nutrients and out compete the algae for its food. Your lights need to be on 8-10 hrs a day. I leave mine on for 10-12 hrs a day but my tanks are stuffed with plants.
One of the ways to get rid of the algae with out chemicals is to reduce feeding (a fishes stomach is the size of one eye), Very thorough gravel vacuum and water changes. but I would stop the chemicals. Even if it is killing the algae the dead algae just makes more food for more algae

It's also very hard on your fish.
But if its just on rocks or driftwood I wouldn't worry about it

Carol