Worry-Free Feeding - You can walk away knowing your fish has been properly fed and cared for. Easy to install and program - includes a simple start-up guide, step-by-step installation instructions stage, Interchangeable feeding chambers - Includes 2 sizes of feeding chambers, small (50ml) for the relatively small aquarium feeding chamber to ensure food is always fresh, larger (100ml) milliliters) so you don’t need to buy another feeder for those with larger aquariums. in stock or if you plan to expand your aquarium in the future. Adjustable volume control - delivers the right amount of food to ensure your fish are properly fed Battery life - Can run on battery (not included) for hours month.