I can see how a nutrient spike could be an issue, that could be a lot of die off all at once. Before I used Algaefix I had scrubbed as much as I could off the rocks and let it collect in a filter sock. I had plucked and dipped for months and was getting nowhere. BTW, I just had hair algae. 
		
	
		
		
		
		
		
	
		
		
	
	
	 |