I dont feed a lot. Since my only eater of those frozen foods is my tomato clown (the blenny grazes on algae and the manderin eats his pods
) I only throw in a quarter cube of the frozen stuff at a time. he doesnt always eat it all but I do have hermits and stuff. as for the anemone, it gets a silverside, or other meaty treat 3 times per week.
I dont know whether the test runs free or total PO4
, but unless its a bunk test kit due to storing, packing or something else that could cuse it to go bad i would trust it because its from salifert