Filter Mats will protects your Pump and removes Debris from the water before it reaches your pump. When you keep the debris from the pump, you keep your pump running at high-efficiency. Watch your waterfalls, if it starts to slow down it is telling you that need to rinse out your filter mats. Just take it out and rinse it of with your water hose.There is a lot of beneficial bacteria growing in the filter mats, so you do not want to rinse out anymore than you have to as rinsing the filter mat will rinse out the bacteria also. Only do as needed.
You only have to change your Filter Mat approximately every 3 years.