The world of aquarium 

Pets liven up a living space but they also require tons of care and attention. If you are one of those people who simply do not have the resources to devote to caring for a dog or cat but you long for a pet, try getting pet fish. They don’t need to be groomed, housebroken or taken for walks. 

Watching the fish in an aquarium is a relaxation for persons of every age and interest. It is almost like you go into a trance when you watch them. Statistics show that collecting fish is the second largest hobby in the world. There are over 25,000 species of fish.

Fish are pets that do not require much care, and an aquarium can add to the decor of a room.  The wonderful thing about fish is the large assortment of shapes, sizes and colors. The behavior of fish also varies with different species. The reasons why fish are so popular as pets is that they are relatively inexpensive to keep, inexpensive to feed, as well as they keep the environment clean and need relatively a small space as compared to other pets. They are welcome anywhere you live, be it a rented house, flat or apartment.

There are over 25,000 species of fish. They are divided into three groups; bony, cartilaginous and jawless fish, the size ranging from a 45 foot (whale shark) to a 8 mm long (dwarf gopi). However, only four types of fish are kept in the home aquarium:-

Tropical Fish - are fish that live in either salt or freshwater but needs warm (tropical) medium temperature to live.

Coldwater Fish - these fish can be salt or fresh water fish which needs colder water temperatures.

Marine Fish- these are fish that live in salty seawater. Most commonly, marine fish need tropical climate.

Freshwater Fish- these fish live in freshwater and are usually the fish that you would find in inland rivers and streams of most continents. They can be as colourful as marine fish and yet need less care. Most freshwater fish in the ornamental hobby are tropical fish, which require a heater. 

In short, the types can be Tropical Freshwater species, Tropical Marine species, Coldwater Fresh water species and Coldwater Marine species. Broadly the most common classification is Fresh water fish and Marine water fish.

Some of the most common fresh water aquarium fishes are the gold fish, Koi (common carp), guppy, molly, swordtail, angelfish etc. Among the Marine aquarium fish species, damsel fish, clown fish (anemone fish) etc are best for beginners where as dragonets and lionfish should be kept only by experienced breeders with large tanks. Sharks, rays, batfishes etc should be avoided. Fresh water species are easier to keep than marine species. Many marine species will be completely incompatible and necessitate careful selection of species when choosing.

Deciding on keeping fish is the easy part, but deciding on what kind of fish to get, from the numerous species available is difficult. It is always better to get an aquarium ready before buying fish as the fish needs to have a ready environment to live as soon as we bring them home.

The biggest consideration when setting up your aquarium is to decide whether you want to house tropical fish or cold water fish. Both Fresh water and Marine species can be either Tropical or cold water i.e they may need either warm or cold temperatures to live. Some fish are very hardy and relatively easy to keep, while others are so fragile that a temperature drop of a few degrees will kill them. Choose fish for your tank that are fairly hardy and that require the same environmental conditions. Some fish may not be compatible when put together. So you must make sure the fish that you choose for your tank are all compatible with each other.

Once you have your aquarium completely set up with or without a heater, you can decide on the fish to put in it. There are many different tropical fish available in the market. Although they need a heater, they are often more colorful than cold water fish.

A fresh water tank is easier for beginners than a salt water or marine tank. Fresh water fish are easier to manage than the marine species. For the beginner, any of the popular fresh water live-bearing fish, especially guppies, mollies, and so on or gold fish, angel fish etc will be the best. If one needs some fish more colorful, white cloud Mountain fish is another option. All of these fish are fairly hardy, and can live at room temperatures. But most of the ornamental variety of freshwater fish is tropical, which require a heater.

Most of the marine fish species are tropical. Among the Marine aquarium fish species, damsel fish, clown fish (anemone fish) etc are best for beginners where as dragonets and lionfish should be kept only by experienced breeders with large tanks. Sharks, rays, batfishes etc should be avoided. Many marine species will be completely incompatible and necessitate careful selection of species when choosing which fish to keep in ones aquarium.

Things to remember before buying fish:-

Once you have decided on a particular species of fish (either Fresh water or Marine) to keep, the next thing is to pick out healthy ones from the lot for sale. It is always better to avoid buying from a store which smells like fish as there may be dead or dying fish around. Avoid fish with cloudy eyes, faded or dull, with open sores and spots on their body. Avoid buying fish that are sluggish or appear to be shivering or the ones that are floating belly up. Take a good look at all the fish in a particular tank. If any appear sick, don't buy any fish from that tank. Choose an active, alert fish. Make sure the fish you choose will be compatible with each other. Characteristics of certain species also matters. Some fish are social but some others will kill each other. If you would like to keep some aggressive variety, be sure to keep them by themselves. Try to get fish pretty much the same size. When you purchase new fish it is better to keep them away from the others a few days to monitor them for diseases.

Diet:- The right kind of food will increase the activity and longevity of your fish and help them adapt quickly to the aquarium environment. It also helps in keeping your fish healthy and bringing out their best colors. There are a variety of foods available for your saltwater and freshwater fish. It is important to know the types of foods your fish need and how much food they need.

Food may include live foods and processed foods. Live food consists of plants, animals and microorganisms that do not cause harm to the fish. Live foods are always better than dried processed foods as they contain better quality of protein than dried foods. Processed foods include fresh, frozen, freeze-dried, and canned foods. Fresh foods can be small bits of meats, vegetables and fruits like beef, chicken, pea, beans, peeled apple etc. A canned food provides a balanced diet and comes in a variety of forms such as flakes, pellets, granules etc. Among canned foods flaked food is the most common food used and is best for small fish. Pellets such as the floating ones and sinking ones are suited for big fishes. Frozen diet such as shrimp or bloodworms provides a good source of digestible protein. Insect larvae, worms, meats etc are available in freeze dried forms. They should be moistened before feeding.

Most fish should be fed two or three times a day. Some fish have slow metabolisms and need be fed only once a day. eg. Goldfish. Fish need only a small amount of food at a time. Sprinkle food over the top, wet them if needed. Feeding more than needed will dirty the tank. Stop feeding when they stop eating should be the rule.