The spectrum on the bulb you posted is only 5000k, a good start but I have found that macro grows best under a 6500k spectrum. When I was using a 5500k bulb I had tremendous amounts of cyanobacteria growing in my fuge, and my chaeto barely did anything. Since switching to the 6500, my chateo has probably quadrupled in size over the last few months. But like cuttlefish said, it could be because that since theres more water volume the nutrients aren't as potent in the water thus making it harder for your greenery to pull them out.