In the best case, aquarium fish are much better off than their owners: they have no existential fears, a nice choice of partners (free of jealousy), nothing else to do and a healthy diet (no fast food chains).
But what does “healthy food” mean anyway? Even with humans we don’t exactly know, or else we actively avoid it, because terms like “organic vegetables” and “wholefoods” aren’t as attractive as “´having a barbecue” and “delicious pizza”.
With fish, the matter is actually not as simple as with humans. We are basically ONE feeding type, even if Asians cannot digest milk as easily as Western Europeans or Mexicans only find food that would get us into hospital with chemical burns tasty. In fish, there is competition for food, which has led to specialisation. For example, there are fish that feed exclusively on the scales of other fish (Perissodus microlepis from Lake Tanganyika) or sea creatures that only eat certain coral polyps (butterflyfish). However, most fish species show a different feeding behaviour: they eat whatever is available! For example, discus and other cichlids in the same biotope feed in the rainy season on, among other things, the fruits of trees they would only be able to reach by jumping metres high in the dry season. In the dry season, the same fish switch to a bottom-oriented diet and eat detritus (organic matter on the bottom). Many small fish species like the neon or danionins are typical plankton eaters, snapping at anything near their mouths. Since these fish and their food are small, they have to eat practically all day long, just like a hummingbird that has to eat every 15 minutes in order not to starve. Predatory cichlids, on the other hand, need food less often because the fish they eat last longer.
Now which of these factors are important for us aquarists when caring for fish?
First of all, the frequency of feeding is not insignificant. If you keep small fish species such as ornamental tetras, neons or the celestial pearl danio, you actually need to feed them three times a day! The only thing to remember about the amount of food is that the fish really do eat it up completely within a few minutes. And by the way: 30 minutes are not “a few” minutes! Fine sinking granulate is ideal because it behaves a little like plankton and moves around. It’s okay to feed larger fish species twice a day. Here, too, it’s important to remember that feeding is not being done correctly when the substrate is covered by sinking food. If you keep medium-sized and large predators (Nimbochromis, Astronotus, etc.), it’s fine to feed them once a day and even let them starve for a day. This corresponds 1:1 to the natural nutrition.
Variety is is the spice of life
Scientists have studied what the various fish species eat quite extensively. They found that many omnivores help themselves from an almost inexhaustible food spectrum. Again, this varied during the dry and rainy seasons of the region. In the aquarium we will unfortunately not be able to copy this food diversity of several hundred organisms. But feeding ONE main food is definitely not enough! A trick that works for a lot of experts is to buy three types of food, which count as their breakfast, lunch and dinner. The most substantial food (e.g. krill) is given as a hearty breakfast, a mixed staple food at lunchtime and a light plant food in the evening. If you also feed frost food, live food or plankton food (JBL PlanktonPur ), you come very close to the variety found in the wild. Many people are not aware that one type of dry food contains up to 54 raw ingredients, as opposed to one type of frozen food, which contains only one raw ingredient.
How does each fish in ONE aquarium get the right food?
Some aquarists face the following problem: In their aquarium, herbivores and carnivores swim together and receive the same food, although they have opposing requirements. These aquarists will just have to train their fish, so that the carnivores always come to feed on the right and the herbivores always come to feed on the left! Fat chance! But our friends in the aquarium do exactly what they are not supposed to: the herbivores make a beeline for the food that contains (fish) meat. So what can you do? Let’s take a look at another species. Wolves are not known to be herbivores and yet they eat grass from time to time. It’s equally good for predatory fish to eat plant food too. It’s more of a problem the other way round. A herbivore that eats too much animal protein will become obese and may even die as a result. Pond owners who feed their koi on cheap trout (= predator) breeding food are always surprised when the koi slowly take on the shape of puffer fish and they quickly (and wrongly) assume that they have dropsy. The right koi food would contain considerably more plant components and the koi would also retain the typical carp shape. The protein/fat ratio is the decisive factor here. For most aquarium fish, a main diet’s protein/fat ratio of 5:1 is the ideal. Take a look at the back of your fish food packaging and calculate it.
More about sex
To come back to the subject of sex: a healthy and balanced diet increases sexual activity – this has even been scientifically proven. So… bedroom or burgers?
Are you interested in finding out in detail which foods suit your fish? Then take a look at the JBL Themeworld under: Food advisor .
In the shop you’ll find an outline of all the food types available: Feeding .