An aquarist should have a crystal clear idea about how many fish will his aquarium hold and we need to work out how many inches of fish can be accommodated in aquarium. Ornamental fish should have obviously more room to swim in an aquarium and shape of the aquarium tank is more important. It has been estimated that a long and shallow tank will hold more fish than a short deep tank. Oxygen content of aquarium water depends on how easily it can be supplied and the carbon dioxide has to be expelled from the water. “How many fish will an aquarium hold?” is a question that adversely affects the happiness and health of aquarium fish.
A good way of measurement is to use the ratio of three gallons of water to one inch of fish. It is often said that fish tank aquariums will hold less than the stated number of gallons because the equipment, gravel, ornaments, and plants will reduce the water volume. Ornamental fishes in an overpopulated tank may get stressed and will turn aggressive towards each other. A good idea to combat this problem is to select the fish that occupy different levels in tower aquariums so there won’t be any space to combat for. Surface area of the water directly impacts the decision on how many fish can be kept in an aquarium.