Eric,
I also use the API test kit and get the same readings as you for the last 1 1/2 yrs. i don't think the amount showing is going to be a problem. You should have gotten 2 color charts for Phosphates with your API test kit, one for saltwater and one for fresh water. As others have suggested I wouldn't be moving the toadstool around too much. The more you bother it, the longer it wil stay closed up. It just might need some time to go through whatever it is.
Mike