There are basically three breeds of tropical fish and believe it or not they are categorized by their temperament.

Social breeds: These fish will get along with other types of fish. Examples of such fish are Danios, Tetras, Guppies, Swordtails, Mollies, and Corydoras.

Semi-social breeds: These fish get along with other fish that are approximately the same size and are not aggressive. Examples are Barbs, Angelfish, and Gouramis.

Aggressive breeds: You do not want to mix these fish with other breeds. Just keep them in pairs with more fish of the same breed. These fish include Male Bettas, Oscars, and Jewelfish.

Good pet stores can always supply you with more detailed information about what kinds of fish you can keep together. Note that all fish that you purchase should have been kept in quarantine for at least two weeks. Fish that are put up for sale before being quarantined are likely to catch infections. The quarantine period is basically meant to relieve fish from whatever stress that they might be suffering.

An important factor while purchasing tropical fish is the color. You should opt for fish with well defined and solid colors. In case the fish has patterns instead of solid color then make sure the pattern does not have any color fading (or gradients).

Aquariums are the next concern and these require a lot of work. The water in an aquarium must always be clean and well aerated. Fish must always be supplied with ample food. In case you add plants they must get sufficient light and nourishment. Algae control is another chore.

For people who are thinking of keeping tropical fish for the first time you need to purchase certain essential items. These are:

* Aquarium, naturally, you need a place to keep the fish.

* The aquarium stand. It is best not to keep the aquarium resting on a solid surface for efficient thermal conduction.

* Aquarium hood. This is to prevent water evaporation and also to keep the fish safe from pets like cats.

* Water filters. These can be chemical, mechanical, or biological.

* Chemical filters. These filters get rid of gases that can accumulate in water as it passed through the carbon filter. While not essential it is still a good idea.

* Lights. Plants in indoor aquariums need a source of light.

* Decorations. While most decorations are up to personal taste there are some things like backgrounds that are a must in order to hide all the wiring in the tank.

* Substrate. The gravel or sand that is usually found at the bottom of most aquariums.

* Plants. Many marine plants are available today. You can purchase live plants (better but they need extra care) or plastic imitations.

* Heater. Remember that tropical fish come from warm climates so they need the water temperature to be slightly higher than room the typical room temperature in cold places.

* Thermometer. This is to check the water temperature.

* Net. For scooping things (including fish) out of the aquarium. Do not use hands or plastic bags.

* Cleaning agents. A scrubber, a brush, a bucket for exclusive aquarium use.

* Food. If you keep fish in a tank then they need to be fed.

Keep these in mind while taking proper care of your tropical fish.