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Feeding Your Fish

How to Feed Aquarium Fish and Choosing Foods from the Wide Variety Available

(The First Tank Guide)

Fish, like any other organism, need a supply of calories to sustain their metabolism. Properly feeding your fish helps them to stay healthy and is helpful in maintaining your aquarium. It is important to know the types of foods your fish need and how much food they need, which differs from species to species.

In most cases, fish only need to be fed once a day, and you only need to feed a small amount. Your fish should be able to get enough nutrients from the food they can consume in under two minutes, as long as the food provides for their nutritional needs. Food that stays in your tank longer than that can get caught in your gravel, decorations, or filter and will begin to decay, contributing to poor water quality. This poor water quality will increase disease susceptibility and filter maintenance. It could also increase the need for water changes, which in turn stress the filtration system and the fish, again increasing disease susceptibility. Small, regular feedings provide fish with the nutrients they need and keep your tank cleaner than large or more frequent feedings. Over feeding can also contribute to algae growth, which can be unsightly, remove vital oxygen from the water, and increase your tank maintenance chores.

Most fish, like most cold blooded vertebrates, are primarily carnivorous, consuming mostly insects, insect larvae, worms, grubs, various shrimps and similar animals, and smaller fish, some even consuming small amphibians, reptiles, birds and mammals in the wild. However, almost all fish also graze on live plants, and there are very few that do not consume at least some algae. So, you can see that most fish are really omnivorous and need to get foods that contain both animal and vegetable matter to remain healthy. Like many children, a lot of fish would prefer to have a nice diet of rich meaty foods and push their vegetables under the table cloth, but this is not available in nature and should not be provided in the aquarium. Though there are fish that are more herbivorous or more carnivorous, there are few fish that are strictly herbivores or carnivores.

There are hundreds of food options for your pet fish, and a combination of foods from this selection is necessary to provide your fish with the nutrients they need. All of these foods fall into two broad categorizations of fish food: live and processed, which can be broken down further as described below.

Live Fish Food

Live food consists of plants, animals, and microorganisms that are living in your tank - or at least live when you introduce them to your tank - that your fish can eat. It is important to make sure that the live foods you provide for your fish provide all the nutrients that your fish need to remain healthy and to grow properly, and do not pose a risk to the fish. Many live foods, particularly feeder goldfish, are very common vectors for disease.

Many fish will graze a little on live plants and algae growing in your aquarium, but some herbivores will voraciously eat any live plants you put in the tank. Other fish will feed on microorganisms that are free-floating in your aquarium water or growing on the surface of plants and decorations. Still other fish will gladly eat worms, snails, and/or other invertebrates that are introduced to the aquarium. Many pet stores also provide a variety of insects and insect larvae that are of nutritional value to fish.

The most common live foods used in the aquarium hobby are live feeder fish. These fish often do not receive the care they need to remain healthy and are often carrying diseases or parasites that could, in turn, infect any fish that eats them. The best way to spread a disease from one fish to another is for a fish to eat an infected fish! Also, in many areas, the live foods that are available are very limited in variety. A diet of just one food is almost guaranteed to be short on some vital vitamins, minerals, or other nutrients that your fish need.

Processed Fish Food

There are many categories of processed foods, including fresh, frozen, freeze-dried, and canned.

Fresh foods include meats and vegetables with minimal processing. Many fish will go wild for small (relatively) bits of beef, poultry, seafood, or game meats, but you don't want to cook these foods in most cases. A lot of fish will also enjoy bits of fresh vegetable matter, such as raw potato, squash, zucchini, pea, bean, apple (without the peel or seeds), and spinach. Again, as with live foods, you need to make sure that the diet you have selected will meet the nutritional needs of your fish.

Frozen foods are available from most pet stores in a wide variety - from shrimp and squid to spirulina algae and vegetables to processed, vitamin enhanced staple diets to aquarium delicacies like sponges and insect larvae. The selection of frozen foods available can provide a varied and stable diet for most fish, and the processes that the foods go through when freezing greatly reduce the risk of disease transfer when compared to live foods or fresh seafood, wile maintaining a high nutritional value.

Many of the foods available as frozen foods also have a freeze-dried counterpart. These foods have all of the moisture extracted from them during processing so that they have a long shelf life and can be stored easily. Many worms, insect larvae, crustaceans, and meats are available in freeze dried forms. One disadvantage of freeze dried foods is that the freeze-drying process often strips vitamins from the food as well, so freeze dried foods are not likely to make a balanced and complete diet. Remember when feeding freeze-dried foods, that these foods can absorb a lot of water, and will fill up your fish a lot more than you would think when looking in the package. We recommend that you moisten freeze-dried foods before feeding them to your fish to keep your fish from overeating and making themselves sick.

Canned foods are often the best for a fish's staple diet. The foods are engineered to provide a complete and balanced diet for your fish and are available in a variety of forms: floating pellets, sinking pellets, granules, tablets, and flakes.

Regardless of the type of foods you decide to feed your fish, you should provide them with a variety of foods. Variety in the diet reduces the chance of any nutritional shortcomings of one or more of your selected foods becoming a health or longevity problem for your fish. Providing a variety of foods will also reduce the chances that your fish loose interest in the foods that they are offered and go on a "hunger strike."

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