Hi Nancy! The green dye is an additive to the material that is used as a tracer. It can vary quite a bit, just based on how much of the dye the tech adds to his tank.
The actual material is always mixed at the same rate. It has nothing to do with the concentration or efficacy of the material. As always, our service is warrantied for 6 months so if you have any other concerns, please let me know. Thank you!-Jen