Feeding Fish in Your Fish Tank

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Food is the source of your fishes nutrition, so using the right foods in the right quantities has a direct effect on the health of your fish

Flake fish food

The food that enters the aquarium is the main source of waste and toxic pollutants such as ammonia and nitrites in the aquarium. If the quantity of food is increased then so does the level of pollutants. Overfeeding is the main cause of new tank syndrome and bad water quality in most aquariums. For this reason it is vital that the fish are not overfed, particularly in a new aquarium without a mature filter.

The correct amount of food to feed your fish varies with each aquarium so there is no set rule for feeding. In a new aquarium, the fish should only be fed once or twice a day and only as much as they will eat in a few minutes. If any food sinks to the bottom of the aquarium or is left on the surface after a few minutes then there is too much food going in the aquarium.

Once an aquarium is matured, normally after a few months, the frequency of feeding can be increased. Although one or two feeds a day is sufficient, feeding little but often is preferable for many fish. The times of feeding do not have to be regular, in the wild fish do not feed at a set time each day! Generally speaking, smaller fish require numerous small feeds whereas larger fish require larger feeds but less often. Some large cichlids such as Oscars only require feeding every other day when fully grown.

There are a number of different types of food available for aquarium fish and choosing between them can be a little tricky. A mix of foods is best for an overall diet and different foods have different nutritional values for fish.


Flake Fish Foods

Flake fish foods are a mixture of food sources, normally with additional vitamins and minerals, which provides a good balanced diet. It is possible to feed only flake food and still provide all the basic nutritional requirements of most fish. In most cases, flake food will form the main diet of your fish and additional foods can be used as supplementary feeds. There are a number of different brands of flake food available and some are noticeably better quality than others. It is normally best to choose a well-known brand and not a cheaper alternative.

Live Fish foods

Bloodworm, daphnia, and brineshrimp are all popular live foods and are available from many retailers. These foods are normally sold in small amounts and will only last for a few days before they start to die. If they are kept in a cool environment, such as in a fridge, they may last a few days longer. Most fish will noticeably enjoy live foods and they are a good source of protein, which is used primarily for growth and repair. Live foods can be fed as a supplement to a main diet or as a 'treat' food. Before purchasing live foods it is worth checking to see which days your retailer receives deliveries, that way you can obtain fresher food, which can be kept for longer.

Frozen fish foods

There are a number of different frozen foods available and these are also normally high in protein and make a good supplemental food. Bloodworm, daphnia, and brineshrimp are ideal for smaller fish and foods such as mussels, cockles, shrimp and lancefish are available for larger fish. Foods that are higher in protein content (live foods, frozen foods & growth foods) also result in higher amounts of waste in the form of ammonia and nitrites. For this reason, they should not be used as a main diet but as additional feeds two or three times a week.

Sinking Fish Foods

Pellet and tablet or wafer foods are available which are designed to sink to the aquarium floor. These types of food are ideal for bottom feeding fish and catfish. Care should be taken when feeding sinking foods, as it is easy to overfeed without knowing how much has been eaten and how much has found its way into the substrate. To avoid this, sinking foods should only be fed every other day and placed in a visible area where any excesses can be removed after around an hour.

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