3 Steps to Find a Pool Return Line Leak With Dye

Turn off the pump and let the water settle for a few minutes. Squirt pool dye or food coloring directly at the return fitting where water normally comes out.

Watch if the dye gets sucked into the fitting or follows a crack. With the pump off, there is no pressure pushing water out, so a leak will pull the dye inward.

If you see nothing at the fitting, check the valve at the equipment pad. The leak may be there instead of in the pool. Avoid red dye, as it can stain light plaster.