I have had a 15g column up and running for about 6months now , I have 2 clowns and just got a small yellow watchman goby , I have a mushroom , a pulsing Xenia , and 2 hammers in my tank ,the corals have not been growing but have not been dying either , any suggestions as to what I can use to light my tank and support coral growth ? I am shooting for around $100 to $200