The algae bloom is caused by organic buildup in the water from over feeding, something hidden died, poor filtration or some mixture of causes. In order to correct the situation, raising water temperature, reducing lighting period or a bag of carbon in the sump will individually not be sufficient. Reduce your feeding schedule. If you can afford it and want to run carbon and or Purigen, get a BRS reactor and small power head. That is far more effective than a mesh bag in even a high flow area. Keep up the water changes to help export the organics and the algae will go away.