The most frequent question asked by hobbyists is, “How much do I feed my fish?” The reason for this is simple; not feeding their fish properly is the most common error hobbyists make. Most fish are either over or under-fed. So, what is the proper method of feeding your fish?
The answer to that question depends. There are two basic types of feeding among the fishes kept in aquaria.
Grazers
The vast majortiy of fish kept in aquaria are grazers. They eat fairly continuously throughout the day, never eating to satiation. The common liverbearers, tetras, barbs, many of the catfishes, and most cichlids fall into this category. Such fish eat small amounts at a time and “graze” during most waking hours. Basically, they nibble continuously. These fish are easily overfed. Their stomachs are not large and can’t hold a large amount of food. They digest food rapidly, constantly eating and digesting and eating more. They tend to have small mouths since they don’t eat large morsels at once.
Grazers should be fed small amounts several times a day. They should never be fed more than will be cleaned up in two minutes. But, since they have small stomachs and digest food quickly, they should be fed many times a day. This mimics nature where the fish eat almost continuously throught out the day.
Gorgers
The less common mode of eating is typified by the gorgers. These fish are adapted to eating very large, but very infrequent meals. Oscars are representatives of this type of feeder. They have large, often extenisble mouths. The can eat large bites. After gorging on a large meal, these fish often spend days digesting the large meal, spurning additional food.
Gorgers, such as Oscars, pike cichlids, and arrowana, should be fed large meals but only infrequently.
How much and how often should I feed?
Feeding is more an art than a science, but there are ways to determine how much and how often to feed your fish. These instructions apply to grazers. I’ll deal with gorgers later.
First, determine how much your fish will eat at a time by starting with small amounts and observing them eating. If the amount fed is eaten immediately and the fish seem to searching for more, then feed a bit more. Continue this process until the fish refuse the additional food. Remember the total amount fed. This should be the amount of food your fish will get first thing in the morning. Thereafter, I recommend feeding your fish whenever you pass the aquarium, but only a tiny amount, less than the first feeding. Observe the fish. Learn to feed them only the amount they will eat immediately. You may find your fish eating less each time you feed them. Adjust the amount accordingly.
As time passes, your fish will train you to feed the proper amount. Your fish will tell you if they are hungry. Fish racing along the front of the aquarium frantically following you as you pass by are very hungry. Fish that ignore additional food or don’t react to your presence by swimming to the top to get food aren’t hungry. Additional food will simply be wasted.
One factor that will affect your feeding is the mix of fish you have. If you have surface feeders and bottom feeders, it is sometimes necessary to feed the surface feeders more than they can eat at one time so that food reaches the bottom feeders. Another solution is to feed a rapidly sinking food to reach the bottom feeders. Many bottom feeders are also noctural eaters. You can feed them after lights out when the other fish won’t compete for food.
Feeding gorgers requires feeding them to satiation and then withholding food until they are hungry again. This may mean only feeding every other or even every third day. The trick is to continue feeding them until they quit eating. Then, allow the fish time to digest their large meal. When the fish begins to prowl and actively follows you when you approach the tank, feed it again, also to satiation.
The key to good feeding practices is observation. Watching fish eat can be fun. If you don’t enjoy this part of the hobby, then perhaps someone else should be feeding the fish. By carefully observing the fish eating you can often discover problems before they become fatalities. A fish that normally eats aggressively that suddenly ceases to eat may have a problem, maybe disease or aggression from other fish. Sometimes it can be something more pleasant such as guarding eggs or, in the case of mouth-brooders, a mouthful of eggs. In any event, the behavior of your fish at feeding time can tell you much about the health of the tank and its inhabitants.
Feeding Fry
Fry can often by fed the same foods as adults, except it must be ground into smaller pieces. All of the flake foods can be fed to fry as long as they are ground into powder between your fingers while feeding the fish. Crumbles can also be pulverized to be fed to fry, but the fry powders are already ground into appropriate sizes for fry.
How Do I Introduce a New Food to My Fish?
Often, fish become accustomed to a particular type of food and are reluctant to take a new food that might look, feel, and taste differently. This is particularly common with cichlids. They frequently become habituated to a food and refuse to accept anything else. The new food remains untouched and finally rots and the hobbyist is frustrated.
There is a simple procedure to get a fish to accept a new food. It’s called starvation. Now, that sounds brutal, but as ectotherms, coldblooded animals, fish can go for days without food without lasting harm. If your fish will not take a new food when offered, simply quit feeding the fish for about three days. Then, offer a small amount of the new food. Continue to periodically offer the new food until your fish takes it.
In general, it’s wise to offer your fish a variety of foods so that they don’t fixate on a particular food. If your fish are used to a variety of foods, they are more likely to accept a new food. And, a variety of food is better for your fish.