Coralline algea going away

[Ruth]

Yes I have tested for phosphate and it is at less than .03 ppm.
My ph is holding steady and that is why I have been reluctant to dial back the reactor.
I have been leaning towards the lighting myself as there is a noticable difference in appearance to the 2 bulbs. The Giesemann has a much more yellow look to the naked eye. I don't have a lux meter or have access to one so can only go by appearance.