Manufactured fish foods contain a bewildering mix of
ingredients and often claim to contain all the necessary nutrients, vitamins
and protein for healthy fish but what in proportions quantities should these
ingredients be? Read on....
Water
Surprisingly in dry foods, water content ranges from 5-15%. If
the water content is higher than this, the food begins to food deteriorate.
Flake can absorb moisture from the atmosphere. As it does so, bacterial action
begins to break down the food eventually turning it into a moist dust. It is
for this reason that dry foods should be stored in tightly sealed containers
and it is best to avoid purchasing a large tin which although may be more
economical, it may disintegrate before it is fed to the fish.
Fats
Nominally this should be less than 3%. Although carnivores can
consume fats up to 6%, a concentration of fats above 3% can be be harmful to
the liver and reproductive organs of herbivores.
Fiber
The fibre content, which stimulates digestion, should be
slightly higher than that of fat. 2% is usually considered a minimum but 4% or
more is desirable.
Protein
This depends on the primary diet of the fish. Foods for
carnivores should contain at least 45% protein. Herbivores require less
protein, around 25%.
Calcium and
Phosphorous
Essential for growth and skeletal strength, these ingredients
are included as fish meal or processed fish bone and are present in quantities
of up to 10%.
Vitamins
It is the ratio of vitamins that is important in fish foods
however, few products list this information preferring instead to state
"nutritionally balanced." Outlined below are some of the more important
vitamins required for fish and an explanation of what they do.
