And you thought talking about worms and larvae was harsh. Now it's nutrition! Like all living animals, fish have dietary requirements for protein, fat, carbohydrate, vitamins, and minerals. In their natural environment, fish will meet their own needs by foraging as needed.
In the home aquarium, fish rely entirely on you to provide their dietary needs. And that doesn't mean feeding them potato chips or corn flakes. You need to make sure that your fish are properly fed (that doesn't mean overfed) so that they are at their maximum strength and vitality. You want active and alert fish. They need consistent water conditions, good aeration, and proper nutrition.
Protein makes up a major part of all animal tissue. A constant amount of protein is needed in the diet to maintain normal growth. As with many animals, younger fish in particular require more protein in their diets than larger, older fish. Fats and carbohydrates are important sources of energy for fish. Vitamins and minerals fulfill the same important roles in fish as they do in mammals. They provide the necessary building blocks for proper metabolism and skeletal stability.
There are many different types of food for your tropical freshwater fish. Here are how the different categories break down (examples of each category follow in parentheses):
Insectivores will eat flake food, red worms, white worms, earthworms, tubifex, brine shrimp, mosquito larvae, and fruit flies. (Jack Dempseys)
Carnivores will consume almost any kind of seafood—crab, lobster, oysters, and clams, (oscars)
Herbivores will eat canned vegetables, like beans, fresh spinach, broccoli, and cauliflower, (most community fish, i.e., angelfish, bettas, neon tetras)
Omnivores will eat all of the above, (goldfish, catfish)
The Four Food Groups
Just like us, in the aquarium world, food is broken down into four major food groups. However, as you might have guessed from their gastronomic tastes, their food groups are somewhat different from ours.
The four different categories of food are flake or dried foods, frozen or freeze-dried foods, live foods, and household foods. Of these, the most harmful to your fish are the live foods. These can potentially carry diseases or parasites that can infect your fish. The following is a brief description of each category.
Flakes or Dried Foods
No, not corn flakes or frosted flakes! Fish flakes are commercially prepared foods that contain the three basic requirements of proteins, fats, and carbohydrates. Many are also supplemented with vitamins and minerals. These foods come in many varieties, depending on the type of fish (carnivore, insectivore, herbivore, omnivore). Many are aimed at specific species of fish, i.e., koi, goldfish, angelfish, oscars, etc.
They also come in many forms, depending on the size or feeding behavior of the fish. Flakes, tablets, pellets, and crumb forms are available. For example, koi, larger goldfish, and larger predatory fishes should be fed pellets as opposed to flakes because they prefer to consume a large quantity. In addition, fish that feed on the bottom may not venture to the surface for flakes, so they must be fed pellets or tablets that sink to the bottom.
All of the community fish reviewed in this book will survive on flake foods. However, if you want active, colorful, healthy fish, you should vary their diets. Flake is best as a staple (or basic) food, but you should make every effort to substitute other foods a couple of times a week to enrich your community fish.
Live! It's Food!
While live food may sound disgusting to you, it really is an excellent source of nutrition for the tropical aquarium. However, live food may carry a heavy price. Many experts feel that live foods may carry diseases that will infect your fish. To insure against this, live foods can easily be obtained from your pet store. You shouldn't ever collect foods from nearby ponds or lakes, no matter how harmless it may seem. The only two live foods that generally do not run the risk of carrying a disease are earthworms and brine shrimp. These are easily obtainable and will provide an excellent addition to your fishes’ diet.
The following section is the Joy of Cooking of the tropical fish world. Here's how brine shrimp, white worms, larvae, and other creepy, slimy delicacies are grown or cultivated. These will come in handy as you become a more experienced aquarist.
Mmmm! Shrimp! OK, so they don't take theirs with cocktail sauce. But shrimp are one of the best sources of nutrition available for fish of any type. Of all the live food available, they are the safest because they do not carry diseases. An added advantage to brine shrimp (Artemia salina) is that you can raise them yourself.
To raise brine shrimp, it is best to follow the instructions accompanying the eggs. If these are lacking, follow these simple steps:
In a plastic or glass container, add 12 ounces of iodized table salt per gallon of water.
Place an operating aerator at the bottom of the container and keep it from moving with a stone, most preferably a smooth one bought in a pet store.
Add 2 ounces of epsom salts and 1 ounce of sodium bicarbonate to the container per gallon of water.
Empty a container of brine eggs into the mixture. Pour them gently because they are small and delicate.
At a temperature of about 75°F, you should have brine shrimp in about two days. You can feed these to your fish as soon as they are hatched. Make sure to continue to feed the shrimp until they are entirely gone. The bigger the shrimp, the happier your fish will be.
Nothing like a nice big plate of oozing, squirming earthworms for dinner. Let's see, do you have chardonnay with that (it's white meat) or a nice Chianti?
These backyard occupants are rich in protein and are a readily available dietary change for your fish. You can search for them after rain showers on lawns, under stones, and around pools and lakes, or you can cultivate them in your backyard.
Gross as it may sound to some (the serious gardeners reading this won't be put off), cultivating earthworms is a really easy, reliable way of finding nutritious and fresh live food for your fish. To cultivate earthworms, dig up a couple of square yards of dirt in your backyard and throw burlap sacks over the tilled soil. Water the sacks until they are soaked every morning of the week. On the seventh day, lift the burlap sacks and you will find earthworms. The best time to harvest is early in the morning before the dew has evaporated.
Earthworms live in and consume dirt, so it is necessary to rinse them and clean them before feeding them to your fish. You don't want to introduce dirt into your tank if you can avoid it. After you get your worms, rinse them off, put them in a jar with holes in the lid, and let them sit for a day or two in a dark shaded area. Rinse them each day removing the dirt from their bodies. If you have small fish, you'll have to cut the worms up—just like cutting up spaghetti for a small child. For the larger fish, don't worry. They'll have a ball slurping those long, wiggly strands in one gulp!
These are long, thin red worms, also known as sludgeworms, that live in mud and are available from dealers. Live tubifex are an excellent addition to your fish's diet. Before feeding them to your fish, you must rinse them thoroughly in gently running water for at least one hour. If possible, rinse them for two additional hours. Tubifex require a lot of work and are very risky because their habitat makes them likely carriers of disease. We recommend that you feed them to your fish only once or twice a month.
Don't attempt to cultivate tubifex yourself! It is very difficult and not worth the risk, as it might cause serious illness if not done properly.
These worms are the cheeseburgers of the fish world. They are filled with protein, but they are oh-so-fattening. These white or beige worms are also known as microworms. You can buy them from your dealer in serving size amounts or you can culture them at home. Starter sets are available from pet dealers or through mail order. It is best to feed these worms in small quantities to your fish. Some experts feel that they can be fattening and cause constipation.
To culture white worms follow these steps:
In a large tray or small shallow tub, place earth and mulched leaves.
Water the soil and place the worms on the dirt. Sprinkle bread crumbs or spread sliced bread on the dirt. Oatmeal has been recommended by some.
Place a sheet of glass over the tray and cover the entire unit with a sheet or blanket. Make sure that the glass is touching every part of the container.
Place the tray in a damp place at room temperature and leave it alone for two to three weeks. Varying temperatures will affect the maturation process.
When you unwrap the tray, the underside of the glass plate will be covered with white worms. Scrape them off and feed them to your fish.
These cultures last for about six weeks. If you suspect that the culture has gone bad, it is very important that you dispose of the entire batch and keep none of the worms. Lack of movement by the worms is a sure sign that things have gone wrong. If they start to smell even worse than they normally do, that's probably another sure sign that something is amiss.
Free Range Earthworms
Make sure that no pesticides or weed killers were used in the area where you are cultivating or collecting your earthworms. Such chemicals will assuredly cause harm to your fish. Some experts prefer to use organic topsoil procured from a local nursery. This is a good idea if you think your local environs have been sprayed with insecticides or other chemicals, especially household cleaners or disinfectants.
No, this isn't the girl from Scooby Doo. Daphnia are water fleas. Believe it or not, these are another excellent live food for your fish. Daphnia should only be fed every now and then to your fish because they can act as a laxative, causing serious digestive problems in your fish. You can buy daphnia from your local pet store or easily culture them at home:
Fill a jar with an inch of topsoil and tamp it down, but don't pack it hard. Some suggest that you add manure or common baking yeast or brewer's yeast as well.
Carefully pour some water into the jar until it is three-quarters full.
Place the jar in the sun for a week until you get a full growth of algae. Wait another week if there is not good algal growth.
Add the daphnia culture and wait 10 to 14 days. After that time, water fleas are ready. To insure that the culture is maintained, never take more than one-fifth of the culture. You must feed the culture, so remember to add manure or yeast several times a week. This culture will only last two to three weeks, but will provide two to three feedings a week for your fish.
You may remember the drosophila from high school science class. These are the larvae of the wingless fruit fly. Like the other live foods, you can sometimes buy them from the pet store or you can culture them at home:
Add agar and some smashed banana to water that you have boiled.
Let the mixture stand for a few day to allow it to gel.
Add some fruit flies, let them sit for two weeks, and you will have a lot of drosophila.
These worms are also known as two-winged fly larvae. These are usually in good supply year-round and can be purchased at your pet store. They are very difficult to cultivate at home, and, of course, we recommend you don't.
As discussed earlier, feeder fish are usually known as feeder or common guppies or goldfish. They are sold from large tanks teeming with these fish. They are sold by the dozens at an extremely cheap rate. These are used to feed large predatory fishes that will not be in the average community aquarium. These are the fish you would feed to the fish listed in the predator section. Before you buy these, discuss feeder fish with your local pet dealer. Many of the fish who eat feeder fish can thrive if fed pellet foods for a long time. However, many of these fish will eventually need real meat. Some substitutes can be found below.
Frozen or Freeze-Dried Foods
In this fast-paced world of ours, even poor, helpless fish are forced to eat frozen dinners. Frozen or freeze-dried foods offer the best of live food without the risk of disease and without the hassles of preparing cultures. No more scrubbing those pots and pans! Many of the live foods previously mentioned—brine shrimp, tubifex worms, daphnia, and bloodworms—as well as mosquito larvae and krill, are available to the aquarist frozen or freeze-dried. They are a great convenience to the hobbyist who wants to provide variety without having to purchase or grow live foods.
In truth, these are an aquarist's best friend. Convenience and safety for you, and maximum reward for your fish.
That's a Spicy Meatball!
Make sure when you treat your fish to household foods that you are not offering table scraps that are covered in sauces: no barbecue or chili sauce, no tomato sauce, no honey sauces, nothing. Not only will they hurt your fish's digestive system (in most cases their stomachs can't handle such things), you'll also foul the water.
No spices either: no salt, pepper, curry, garlic, nothing. Serve it nice and plain, just the way nature intended it.
OK, let's stop all the nonsense right here. No, they can't have nachos, beef jerky, caramel corn, fruit rolls, cheese puffs, chocolate, or even chicken wings. Some of these are trade names. We're talking about real food. Many household foods offer nutritional value and variety to the diet of your fish: fresh, frozen, or canned oysters, clams, mussels, crabmeat, lobster, or bits of raw fish. No canned tuna fish! Tuna is too hard to digest and leaves oil slicks.
While the live and frozen foods are ideal for carnivores, insectivores, and omnivores, household foods are also available for the herbivores. Baked or boiled beans, steamed cauliflower or broccoli, and boiled or baked potatoes are excellent additions. Fresh spinach or lettuce is also good for your omnivorous and herbivorous fish. Carnivores, in particular, will especially enjoy small bits of ground beef or cooked chicken.
These foods must be given in moderation. Remember, you are augmenting your fish's diet with these foods, not creating a staple. Household foods must be diced or shredded so that your fish can eat them. Don't offer your fish table scraps unless they conform to what is listed above.