ROX (carboxy-X-rhodamine) is one of the passive reference dyes providing a constant fluorescent signal that is used for signal normalization during the amplification cycles. The emission recorded from a reference dye during the baseline cycles is used to normalize the emission recorded from the reporter (e.g. EvaGreen®, SolisGreen®, SYBR® Green, etc.) in later cycles in ROX-dependent real-time PCR systems (e.g. Applied Biosystems 5700, 7000, 7300, 7700, 7900HT, StepOne™, StepOnePlus™). Reference dye compensates for small fluorescent fluctuations and well-to-well variations that may occur.
In Solis BioDyne qPCR mixes we use technology, based on ROX, that allows us to use same mix for high- and low- ROX requiering cyclers.
Please check cycler-mix compatibility here if not sure.