cooking live rock

[makana]

I have about 80lbs of live rock that I have been cooking in a tub for over four months now and I am still getting high phosphate readings. I am getting almost no detritus in the tub when I do water changes. When I swish the rocks in a bucket the water ends up tinted green which is the colour of the dieing/dead coraline. What I am wondering is if this could be the source of the phosphates. If I had a light on the tub and the coraline started coming back, would the phosphates stop showing up?

All the reading I have done says to keep cooking until the phosphates stop, but they also usually suggest that it will be done in about three months or shortly after the detritus stops coming out. Does anyone have any firsthand experience that relates?