Color Balance
The Color Balance filter lets you adjust the color balance of an image by shifting the colors between complementary pairs of the primary RGB color values and secondary CMY color values. This method is useful for correcting color casts. For example, if you want to tone down the red in a photo, you can shift the color values from red to cyan.
You can also apply color shifts to shadows, midtones, and highlights independently, which gives you more options for adjusting colors. For example, you can shift the shadows to blue and highlights to orange. In addition, you can use the neutral color eyedropper tool to choose a color that should be neutral gray and the filter will automatically remove color from pixels in a selection.
You can access this adjustment from the Adjustments inspector, the Adjust menu, or by pressing Command + Shift + B.