With the number of different brands available growing all the time, it is important to remember that there is more to a fish food than simply what's written on the packaging. More important is the actual quality of the diet, and this involves more than just its respective levels of protein, oil and vitamins. So when selecting a food for our fish, how can we he sure that it is of a high quality; and more importantly what are the consequences if we mistakenly choose a poor quality one?

To answer the first question requires us to have some knowledge of the Company that has produced the food and how they go about manufacturing and testing it.
Tetra has a fifty-year history of producing high quality fish foods for the ornamental fish industry We also operate the largest commercial research and development laboratories in the world, for testing and improving ornamental fish foods. This means that our foods are not only well researched and manufactured, but that they have also proven themselves to be the best of their kind. Tetra's facilities are unrivalled by any other ornamental fish food producer, and this has led to the quality of our foods being recognized by fishkeepers worldwide.

Quality vs Quantity?

We are obviously very proud of our fish foods, but what are the benefits to your fish of feeding them on a high quality Tetra diet? The answers that there are many benefits, some less obvious than others.

A high quality food will be more digestible, meaning that the nutrients in it are efficiently utilised by the fish, leaving less undigested waste.
Less waste means less water pollution, and consequently less tank maintenance. Poorer quality diets will create excessive waste, clogging up gravel and filters, encouraging the growth of algae and the proliferation of potential harmful bacteria, and adding to the ammonia load.

Another advantage of efficient food utilisation is that you will actually end up getting better growth rates, colour, health, and reproductive success from your fish. This is because with a high quality diet they are getting more out of. a given quantity of feed than with a poor quality one.

For example, if two diets both contain 40% protein (40g per 100g of food) you might think that they are equally matched.

However, if one is a good quality diet and is 90% digestible, and the other is a poor quality one that is only 60% digestible, the figures start to mean less. In the high quality diet the fish will be able to utilise 36g of protein for every 100g of food fed, whilst in the poor quality diet they will only be able to use 24g for every 100g fed. Clearly the fish fed on the high quality diet are going to have more protein available to them for growth, reproduction and so on In order to achieve the same level of performance with the poor quality diet, you would have to feed at least 50% more of it, so are you really saving money with cheaper foods?


Of course, as well as leading to more waste in the tank, a poor quality diet may not provide your fish with the correct nutrition. Deficits, or absences of key nutrients and vitamins, can lead to decreased health and vigour, and by the time this is realised it can be a struggle to bring fish back to their former glory.

Quality Requirements

Knowing the advantages of feeding a high quality food to our fish, it is also useful to be aware of some factors that go towards determining the differences between high and low quality diets.

A high quality food will have the correct balance of nutrients to ensure that it is efficiently utilised by the fish. Balancing nutrients is important, as the quantity of one dietary component can affect the way in which another is used.

For instance, there is a great deal of interaction between the oil and protein in a diet. Protein is used for new growth, as well as acting as a source of energy.

However, when protein is used for energy it results in ammonia production; oil is an even better source of energy for fish, and if presented in the correct proportions it can reduce the amount of protein that is used for energy thereby lowering ammonia production.
However, if too much oil is present the fish will not be able to use it effectively.

There are many examples where getting the correct balance of nutrients is important in creating quality fish food.

The ingredients used to make the food are also critical in determining its eventual quality. There are many different potential ingredients that can be incorporated into a diet in order to provide the fish with its dietary requirements. Using ingredients that do not co the right mix of nutrients, or that contain them in an inaccessible form, will decrease diet quality.
To illustrate this we can take the example of protein.

Proteins are made up of sub-units called amino acids. Amino acids are the building blocks that fish use for growth (through the synthesis of new proteins), as well as being crucial for a multitude of other physiological processes. There are ten different amino acids that have to be included in fish diets in order for them to remain healthy. Different sources of protein contain differing levels of these amino acids, and some maybe lacking in one or more of them. It is therefore very important to select ingredients that are high in all of these essential a acids, otherwise the quality of the diet will be compromised. Vegetable and plant proteins in particular are often lacking essential amino acids, and so if they are to be used it is essential that they are supplemented with those that are missing, either artificially or by including another protein source.

High quality diets such as those produced Tetra, contain the correct mix of all the necessary nutrients, as well as using the best available ingredients. Poor quality diets that do not may not only be less digestible, but they may also potentially lead to dietary disorders.

The final major determinant of food quality comes with the actual manufacturing process. The way that feed ingredients are treated and processed can dramatically affect their availability to fish (and thus their digestibility). To illustrate this we can take the example of ingredients derived from plants.

Many plants contain anti-nutritional factors, which actually inhibit the digestive system of the fish. For example, untreated soybean meal contains five protease inhibitors. Proteases are enzymes that are essential for the efficient breakdown of protein. If these inhibitors are left in the food then they will severely reduce its quality. However; by using the correct processing techniques these anti-nutritional factors can be removed, making the ingredient perfectly suitable for inclusion in the diet. It is therefore very important to thoroughly investigate a feed ingredient before it is used, and then to determine exactly how best to process it, before using it in a fish food.

Tetra's formidable research and developmental capabilities allow extensive analysis of ingredients and, because we have a manufacturing plant specifically dedicated to making ornamental fish food we can use specialised processing techniques to ensure that all ingredients are optimally utilised by fish.
Tetra's latest fish food, TetraMin Pro, is testament to this ongoing dedication to researching new manufacturing and processing techniques.

Traditional flake foods have to heated to over 130oC during the manufacturing process, which results in the destruction of some of the nutrient content (in particular vitamins). This in turn decreases the digestibility of the food, TetraMin Pro is manufactured using Tetra's patented new low heat process that only requires the food to be heated to 75C. This results in a greater preservation of nutrients, energy and vitamins, and increases its digestibility. It also contains L-Carnitine which improves the efficiency with which its nutrients are utilised. In fact, TetraMin Pro reduces water pollution to the lowest level of any aquarium food.

So when choosing which fish food you are going to feed to your fish, remember that they are not all the same, and that it can have a real effect on the condition of your fish and the quality of your aquarium environment.

NOTE: This subject is covered more fully on the FBAS VIDEO,

V.35 FISH FOODS & THE AQUARIUM ENVIRONMENT

click on picture for details

- and you can also buy it on VCD or DVD.


Last updated February 2005

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