In order to understand discus fish nutrition we will cover some basics on the dietary requirements of fish in general before moving specifically into the needs of discus. A discus fish food recipe is included in this article. All animals, whether aquatic or terrestrial, including discus require five basic food components. These are : 1. Protein 2. Fat 3. Carbohydrates 4. Vitamins
5. Minerals. Each food component has a specific function in nutrition.
Protein in Discus Nutrition
Protein plays a very important role in discus fish nutrition. Proteins in discus nutrition are organic compounds made up of small chains of nitrogen containing molecules called amino acids. There are twenty common amino acids, ten of which are essential for life. They are called essential amino acids. The others are called nonessential amino acids. The non-essential amino acids may be used in discus nutrition for energy or broken down into essential amino acids. In general, animal origin proteins contain more of the essential amino acids and are considered to be a higher quality than plant origin protein. The ten essential amino acids are : arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, theonine, tryptopitan and valine. Meat and fish tissues supply almost all of the essential amino acids in sufficient quantity, and including them in the discus nutrition diet insures an adequate balance. Whole egg protein contains an excellent balance of essential amino acids and can be used as the sole protein source in discus nutrition. Discus fry can be raised on egg yolk powder and discus nutrition needs are met. Carnivorous fish need a minimum of 35-45% protein in their diet. Many discus hobbyists are aware of the need for high protein levels in food for their discus fish, but usually do not know why. Newly hatched discus fish fry benefit from a diet with a minimum of 50% protein. This increased protein tapers down as they grow and develop. Proteins not used for tissue reproduction are utilized as energy in discus nutrition. The metabolism of these proteins to sugars results in the release of highly toxic ammonia which is eliminated into the water by the gills (85%) and the kidneys (15%). The ammonia released into the aquarium is a pollutant. It is detoxified by the filter bacteria which use it as a food source. Thus, the use of a very high protein diet in discus fish nutrition puts an additional load on the filtration system and deteriorates aquarium water quality. This is why I emphasize having a strong biological filter in the discus fish aquarium and performing regular water changes. The biological filter in the discus aquarium eliminates ammonia. The water change eliminates the by products of this ammonia conversion process. This is a key to understanding your discus aquarium. Protein in discus fish nutrition plays a key role in the function of the filtering process.
Fat (Lipids) in Discus Nutrition
Fat is vital to proper discus fish nutrition. Fats and oils are important sources of energy in a discus fish’s diet. In discus nutrition, fat contains almost twice the calories for energy production as an equal quantity of either protein or carbohydrate. Fats are also the energy storehouse for the discus fish. Nutrients ingested but not utilized are converted to fat for use at a later time. In addition to being an energy source, certain components of fats are essential in building cell membranes, absorption and utilization of vitamins and production of hormones in the discus fish. In discus fish nutrition, these indispensable components are called essential fatty acids.Homeothermic (warm blooded) animals utilize and store saturated fats containing omega 6 fatty acid groups. Heterothermic (cold-blooded) animals store lipids (oils) containing omega 3 fatty acids. It is these omega 3 fatty acids which are essential in the diet. A deficiency of essential fatty acids results in slow growth, fin deterioration, reduced disease resistance and diminished fertility. The best source of essential fatty acids in discus fish nutrition are fish and crustacean oils.
Fats and oils, when burned for energy, reduce the amount of protein which is metabolized. This is called the protein sparing effect and allows the bodies to more effectively utilize amino acids for growth. Metabolism of fats is efficient and does not result in ammonia production. Fats which are solid at low temperatures are not digested by cold water fish. In discus fish nutrition warm water fish such as discus can utilize saturated fats such as beef tallow for energy purposes. Discus fish eat to fulfill energy needs, not protein needs, and a diet high in fat may meet the energy need before sufficient protein has been ingested. Fats oxidize and become rancid when exposed to heat, air and light. Most dry discus fish foods have low fat contents and are supplemented with antioxidants to combat this problem. Freeze dried foods such as shrimp and krill are also subject to oxidation. In discus fish nutrition freeze dried foods should not be considered as a component of the diet. Frozen foods generally contain well preserved oils and should be used in discus fish nutrition as a part of the discus diet. Dry foods, especially flake foods should be refrigerated. If you open a can of used flake and it smells rancid it is not fit to use. Many brands actually spoil within hours of being opened and exposed to air. Discard it and open a new one, refrigerating after use. We now use a certain brand of flake food made from whole salmon fish high in Omega 3 fatty acids in our discus fish nutrition plan. It does not have the spoiling or other problems associated with many flake foods that cause discus so many problems. It is not made of fish meal which can be processed parts such as scales, fins or bones and other body parts unsuited for other use. To obtain this flake food :
Discus Fish Flake Food
Carbohydrates in Discus Nutrition
Carbohydrates are not a major constituent in discus fish nutrition.The carbohydrate group consists of simple compounds such as sugars and more complex aggregates called starches. Carbohydrates are generally a major component of vegetables, fruits and grains. Carbohydrate digestion requires specific enzymes, which are often not produced by carnivorous animals. In discus fish nutrition the addition of vegetables and grains to the discus diet to supply essential vitamins and minerals will provide adequate carbohydrates to meet their dietary needs.
Vitamins in Discus Nutrition
Vitamins play an important role in discus fish nutrition. Vitamins are organic compounds that do not provide energy but are required by the body of discus fish to produce enzymes and growth factors. The ten B-complex vitamins and vitamin c are water soluble. Vitamins A, D, E and K are classified as fat soluble. The fat soluble vitamins are stored in the discus's body fat. Water-soluble vitamins, if given in excess, are rapidly eliminated from the body. In discus fish nutrition fat-soluble vitamins are less easily eliminated and in excess can become toxic. Heavy supplementation with pure fish oils may produce hypervitaminosis of both vitamins A and D in the discus fish. The water-soluble vitamins are labile to heat and oxygen. The cooking and extrusion of dry foods may destroy 50% of the B vitamins and up to 97% of vitamin C. Oxidation of vitamins during storage may result in a 50% loss during the first three months. Freezing does a good job of vitamin preservation and frozen foods should be a major part off the discus diet. Carotene and xanthophylls are vitamin A precursors found in vegetables, algae and many crustaceans in discus fish nutrition. These compounds are red dyes and will color both the flesh and skin of discus fish, providing brighter colors along with nutritional benefits. In discus nutrition good vitamin sources are liver, eggs, wheat germ, peas and leafy green vegetables. For good discus fish nutrition, due to the labile nature of vitamins it is good to add fresh multiple vitamin supplements to any diet you prepare. Do this as a last step before freezing the food.
Minerals in Discus Nutrition
Minerals are an important component of the diet in discus fish nutrition. Minerals are needed for formation of body tissues, particularly bone and cartilage. Many minerals are absorbed from the water.Others are supplied to the discus by a varied diet. Calcium and phosphorus are the two minerals required in the largest quantities and are therefore the ones most likely to be deficient. Calcium absorption in discus fish depends upon adequate available phosphorus. These minerals should be supplemented as one part calcium to two parts of phosphorus. The correct Ca:P ratio is found in whole fish, crustaceans and in organic supplements such as bone meal (this is not the same ingredient as fish meal).
Energy Sources in
In discus fish nutrition, proteins, fats and carbohydrates supply energy. The measure of energy for each group is measured in calories, with fats containing twice as many calories as proteins and carbohydrates. It is not necessary to calculate how many calories your discus fish consume. Daily feeding of 3% to 5% of the discus fish’s body weight using a quality diet is sufficient for proper discus fish nutrition. All fish, including discus fish need fewer calories than terrestrial animals because they are cold blooded and do not burn calories to stay warm. Also their water environment supports them. Growth, disease, reproduction and increased environmental temperatures all increase energy requirements and should be considered in formulating proper discus fish nutrition plans.