The BiOrb 15 is the smallest in the BiOrb range and holds 15 ltrs of water, making it an ideal starter aquarium. It is available in both standard or automatic moonlight lighting systems. Although 15 litres is a relatively small volume of water it is still possible to successfully keep a selection of tropical or cold water fish. Baby BiOrbs even have the option to change their top and base colour to match in with their surroundings, or to make them really stand out. BiOrb 15 are available in black and silver and the swap tops available are baby blue and tangy yellow.