I am building a manipulate out of a complicated differential equation with three time coefficients K1, k2, k3). I am having a problem with the third time coefficient (k3). My problem. I cannot figure out an appropriate value for the increment. Here is my code. 
 
{{k3, 0.0000119, Style["k3", Blue, Bold, Medium]}, 0.00000010, 0.0000250, 0.0000000050, ControlType->Slider 
As written, my code places the slider bar knob in the middle of the range. Problem being, moving the slider does not move my graph. Not in the slightest degree. What am I doing wrong?