Before buying new aquarium fish at a pet store it would be good to know symptoms of the fish sickness. This is important knowledge for beginners because they can not only rely on the honesty of the seller in pet shop. There is nothing worse than buying a sick fish which in a short time can lead to the extinction of our aquarium. You should buy only healthy fish and try not to rely on sellers opinion, but carefully look at the fish.
If you buy a gregarious species then you must purchase at least a dozen pieces of one kind having predominance of females over males. When you buy fish living in pairs the best is to buy male and female which choose them selfs already (but it is not an easy task to get couple like that).
We never should by to many fish. The fish should have a space to swim and also many hiding places. Generally for one adult medium-sized fish we should have six litres of water in the aquarium or 1 litre of water per 1 centimeter of fish length eg. 10 fish 5cm each requires 50 litters of water in the aquarium. Remember that rocks, roots and other decorative elements taking space and we have to calculate it accordingly.
When selecting fish for an aquarium always check their requirements (pH, hardness, temperature, type of water, etc.), method of reproduction and behavior in the aquar(aggressive, friendly etc.).
These species of fish that do not have many requirements and are easy to breed:
Cichlids recommended for beginners:
Not to difficult are also: