The 7-Day Pyramid Fish Feeder supplies superior nutrition for freshwater aquarium fish for approximately 7 days, when you are on holiday and not around to feed them. After being placed in the aquarium, fish will sense the presence of food within the pyramid, and are attracted to it. Within a few hours, as the holiday block softens, the fish begin feeding on the nourishing food pellets from the surface of the pyramid. These pellets contain a formulation of energy-rich foods, along with essential vitamins and minerals, which are provided continuously during the feeding cycle of the pyramid. Fish feed at will; the more they eat down through the block, the more food pellets are exposed. Approximately mid-way in the pyramid's 7-day feeding cycle, a centrally-located chamber within the pyramid will be exposed, supplying a nutritious treat to add variety to the fish's diet. Directions for Use: Simply place the 7-Day Pyramid Fish Feeder in the aquarium to begin the feeding cycle. One pyramid will normally feed the fish in an appropriately stocked 38 litre aquarium for 5 to 10 days.