Understanding feeding and digestion in fish

When compared to humans, the digestive system in fish is relatively simple. There will of
course be variations that are species-dependent. Some species of fish have teeth. The
teeth in fish are generally adapted for performing special functions. Predatory Catfish will
for instance have small sharp pointed teeth, while the Pacu fish have teeth adapted to
crushing fruits and nuts.
The stomachs of fish are also generally adapted to the kind of food they eat. Predatory
fish generally have sac shaped stomachs that allow them to pack away enormous amounts
of food. The Puffer fish has a stomach that can be inflated with air or water in order to
scare off enemies. Food that is partially digested moves from the stomach into the
intestine. Here it is digested further and the nutrients are absorbed into the body. Theherbivores have an elongated intestine and their systems are more complicated than the
carnivores. Food that is not completely digested and absorbed leaves the body through
the anal opening, together with other waste products produced by the metabolism.
Giving your fish the right kind of food at the right time and in the right amounts is crucial
to their growth and development. In a closed system, the fish have no choice but to eat
what they are provided with. If you want fish that are full of energy, you have to feed
them according to their particular needs.
􀂾 Every type of fish has a specific feeding requirement.
Herbivorous fish require lots of fiber in their diet, while carnivores
require food that is rich in protein. Some predatory fish eat food
only after chasing the live food.
􀂾 Do not make your fish obese. Yes, fish also gain unhealthy
fat from over eating. Some fish like the catfish will eat just about
any amount of food. They become too big and lose health.
Remember that fish in your aquarium do not expend energy
looking for and chasing food. They only move about within the
confines of your tiny little aquarium. So, feed your fish only
according to their nutritional needs.
􀂾 Overfeeding introduces a lot of unwanted toxins into your
system. Mostly, fish are able to take in the food they need within 5-
10 minutes of their feed. Food left in the aquarium after the first 10
minutes of feeding is not needed by the fish, and will collect in the
aquarium as waste; decaying and releasing toxins.
􀂾 Obtaining food can become a problem in a community or
biotope aquarium at times. Hyperactive fish and fast swimmers
will get the first pick in the aquarium. Small fish can be scared
away by larger fish and newly introduced fish may be too shy to
get to the food.
􀂾 Give your fish a variety of food. Feeding fish the same kind
of food day after day tends to dry up their appetite. Besides, they
also need a variety of nutrients, which can be provided only by
rotating the feed.
􀂾 Be very careful when and if you introduce live food into
your aquarium. Many fish species love worms, insect larvae
etcetera and will stay much healthier when provided with live food.
Care must however be taken to ensure that these food varieties do
not carry infections, such as germs or other parasites, in them. This
is very difficult to ascertain, unless you culture your own live food.
So beware when you feed live food to your fish.
Food for the fish has to encompass a large number of nutrients. All these together make
your fish healthy and able to adapt to changing conditions in the aquarium. Remember,
the healthier the fish, the more resistance will they have to disease and infections.