Dye Tabs $0.00 Test for toilet leaks using dye tabs. Drop one dye tab into the tank of the toilet to change the water color. Wait 20 minutes without flushing. If the water in the bowl has changed color, your toilet's flapper valve is leaking from the tank into the bowl and must be replaced. View the instructional video at ebmud.com/leaks. Note: one order will come with two dye tabs. If you need additional dye tabs for any reason (such as for a commercial property or multi-family residence), please contact our Water Conservation team at waterconservation@ebmud.com or 1-866-403-2683. Quantity Add to Cart Out of Stock