IMO, the EG certainly would have contributed. Did you get to the meeting where Julian spoke of old tank syndrome?
Here is the thread where Suzy and I gave a recap of his lecture. This info may be too late for you now, but not for the rest of us to learn from you.
Sorry to hear of your plight. Is it hair algae?
I guess now it's time to do all the things necessary to control nusiance algae. Reduce nutrient input (cut the feeding, check topoff H2O purity), cut back the light (2 days of complete darkness with a cover over the tank - one day of actinics only -->for about a week or more), add PO4 remover, add herbivores (fish,snails,hermits, Turbosnails, Blue Knuckle Hermits, etc.), increase algae production in the Refugium (brighter, 24/7 lighting).
Hope this helps.
