Replace the existing bulb with a brighter one, also called an illuminator, to improve the effectiveness of the fiber optic cable. Refer to your system's owner's manual to ensure your system can handle a brighter wattage before replacing the bulb.
Add a color wheel to the bulb. A color wheel is a motorized disc positioned near the bulb that rotates, changing the resulting color of the light as it turns. This adds a pleasing effect to your pool water because the water color changes at regular intervals.
Switch the fiber optic cable to an LED light to improve the brightness further. LED lights also typically last longer and are more cost-effective over time. Drain the pool enough to access the light and unscrew the lens cap. Wipe away any mold inside the housing and pull out the fiber optic cable. Run the LED wire through the housing until it comes up out of the ground in the electrical area. Slide the LED light into place inside the housing and gently screw or hammer the cover in place, depending on the model. Refill the pool to normal levels and complete the wiring in accordance with your LED instructions for best results.