Good idea to change out half the tank water. I'm not sold on the use of "algae destroyers". Chemicals will kill the algae very quickly, but the decaying and dead stuff just creates more nutrients for the next algae bloom.
I'd like to put in a vote for dealing with algae the "old fashioned way" next time, by beginning an aggressive water change routine. Every week, change half the tank water and start planting fast growing plants that consume a lot of nutrients, like Water sprite (floated), varieties of Hygrophila, Anacharis, Pennywort and Hornwort.
There are natural ways to deal with algae. Those are by far the best.
Just one old "water keeper's" opinion.
"Fear not my child, just change the tank water."