how can i stop algae growing in my marine tank???? i change over 10% of the water with ro water weekly ive tested the nitrate and nitrite and they are saying 0, i brought the new fluval g series filter about 3 months ago and that doesnt seem to help my skimmer is working great and so are my 5 fans. i have very little living things in my tank 4 small fish a spinny star fish and a couple of small anenomes. please help

hi there try testing for PO4 Phosphate thats your problem bud
mecca

Like Mecca said, have you tested the phosphate levels in the water before and after adding salt?
A common cause of algae is phosphate from poor quality RO water, or poor quality salt.

There are other causes but start there.

po4 could still be 0 if you already have an algae problem as it will be absorbing phosphates..

is your tank near a window? what lighting are you using and how old are your bulbs?

I sometimes get a phosphate issues. I buy Rowaphos and that helps get rid of it and it doesn't leak back in to the water once fully absorbed.

my po4 is to high thanks for all your help