cause of algea

[o0jmadr0x0o]

could these rocks that were used in my old freshwater setup be causing my algae and nitrate.
i have a 50g with about 70lbs of live rock and about 30 pounds of this base rock
29g sump with chatoe
CSS 65

http://s153.photobucket.com/albums/s218/o0jmadr0x0o/?action=view&current=100_1624.jpg

i use RO water and do 5-10g water changes a week, but have been doing them more since i got my RO unit, trying to get algae and nitrates to go away

could it be these rocks?

 

[Deanos]

Yes, it could.

 

[Breezp]

rocks
skimmer
bad/old lighting
insufficient r/o water
how much you feed
phosphates

take a pic from any of the above..... algae is a menace

 

[LouZoo51]

How long have you had your ro unit?,also these rocks could be leeching phosphates into your system...