Fish tanks come in all sorts of shapes and sizes. Nano tanks or the very small tanks are great little tanks to keep cherry shrimp, snails, a single betta fish, newly hatched fry or used as a hospital tank. But should not be used as an aquarium, as they are too small and it will be difficult to maintain stable water conditions if more than a fish or two are kept together.
Even small fish, such as those from the danio family or tetra family should not be kept in such small tanks, as danios are fast swimmers needing larger tanks to race in, while tetras although small, are shoaling fish and need to be kept in large schools of 6 -20.
Making these tanks too small.
Check below for larger aquariums which will be easier to maintain.
Check the requirements of the fish you want to keep, before you buy your tank.
Also use the following calculator to help you decide:
http://aqadvisor.com/
Click images for more info.
Various Sized Tanks
25L Aquarium Starter
25L Small Aquarium
