Fish tank hobbyists tend to gravitate toward fish as pets because of the seemingly less-intensive maintenance and care required of these animals. Although fish don't require visits to the vet or walks around the neighborhood, that doesn't mean that having a home aquarium is a hands-off approach to pet ownership. In fact, even the most devoted home aquarium owners may find they are plagued by one or more issues with water quality or fish health.
Much like a swimming pool, aquariums need proper water chemistry and some other conditions to thrive. If there is a slight sway in one direction or another, you can be left with sick fish or an unsightly tank.
* Algae: Algae is a form of plant life that is often a sign of a healthy underwater environment. Many types of marine life feed on algae, and small amounts of it in a fish tank are nothing to worry about. Large amounts of algae may be more unsightly than troublesome. Algae needs a light source to grow, so a good deal of algae in a tank may be indicative of too much light in the aquarium. Relocate the fish tank if it is by a sunny window or door. Otherwise, you may need to reduce the amount of time you leave the aquarium light on. This combined with introducing a few algae-eating species of fish to the tank could correct the problem.
* Cloudy water: Another thing many aquarium owners may encounter is cloudy water conditions. Cloudy water can be a byproduct of many things. However, one of the more frequent offenders is overfeeding fish. New fish tank owners may not be able to determine just how much food to give their fish and may have a heavy hand when shaking the container. Uneaten food breaks down and may begin to decompose and foul the water, particularly if it is not being thoroughly cleaned by the filter. Reduce the food given to the fish and change 25 percent of the water volume to alleviate the cloudy water. If cloudiness persists, have your water tested at the pet store.
* Toxic water: Fish need a careful water environment to thrive. It takes time for the right balance of helpful bacteria to form in the water and time for the water quality to equalize. Water straight out of the tap may be toxic to fish because of cleansing agents. It is important to add water conditioner to tap water and allow it to distill before adding it to the tank. Also, allow time for a new tank to filter before gradually adding fish.
* Too many fish: It's easy to fall in love with all of the interesting fish in a pet store and want them all for your tank. Too often aquariums are crowded with fish, which creates an unhealthy environment. Small fish may each need 2 gallons of water, where larger ones may need 5 to 10 gallons. Err on the side of more space for your fish, and you'll give them the best chance to blossom.
* Mixing incompatible fish: It is unlikely that all types of fish will cohabitate peacefully in a home aquarium. Some fish are prey to other breeds, and there are some fish that are naturally aggressive and territorial. To ensure you do not end up with a tank with one, very large, well-fed fish, it is important to research different species of fish and know which ones can live together and even complement others.