| calcium readings
good day all
I'm having trouble getting a calcium reading.I used an API test kit,(aquarium pharmisutical inc.)pardon my spelling.Problem is .5mls. water then one drop regent untill you see a color change.I did this even shook the tube after each additional drop.There was no color change as i ran out of tube,it was completly full.I would like some one suggest a better test thats more accurate.Mabe the regent was old or I wasnt holding my mouth right,lol.TY everyone | 
