How to Feed Goldfish
To feed your goldfish, grab just enough food that you can pinch easily between your thumb and forefinger. Then, pre-soak the food in order to reduce the chance of digestive upset. If you're using flakes, pre-soak by dipping them in the tank water a few times before fully placing them in the water. For pellets, soak them in a small container of tank water for 10 to 15 minutes before adding them to the tank. Feed your goldfish 1 to 2 times a week if you're using flakes, and 2 to 3 times a week if using pellets.
Learn what types of food your goldfish should eat. Goldfish are omnivores, which means that they eat meats and plants. There are many types of food that you can feed your goldfish, and it can be overwhelming to go into the pet store and see all of the available options. Before purchasing any food, take some time to learn what the different options are. Keep in mind that each type of food has its advantages and disadvantages. Your goldfish's diet should consist of many different types of food. Purchasing different types of food will help you keep his diet interesting and ensure that your goldfish receives all of the nutrients that he needs to stay healthy. Include dry food in your goldfish's diet. Dry food is one of the most common types of goldfish food. Dry food is usually sold in cans and comes in either flakes or pellets. Flakes will stay at the top of the tank and pellets will typically sink to the bottom. Your goldfish will feed at the top and bottom of his tank, so you can use either type of dry food. In general, dry food is fairly healthy for your goldfish, but does not have all of the nutrients that he needs. Because of this, dry food should not be the main component of your goldfish's diet. Since flakes stay at the surface, the excess flakes can be removed easily, making the tank easier to keep clean. Provide different types of live food for your goldfish. Live food is an excellent source of protein for your goldfish, and is considered to be the most important part of his diet. Examples of live food are earthworms, bloodworms, daphnia, and brine shrimp. If not prepared properly, live food has the potential to transmit disease to your goldfish. To reduce the likelihood of disease transmission, purchase the live food from your local pet store, rather than searching in lakes, ponds, or the dirt. Usually, brine shrimp and earthworms are highly unlikely to transmit disease. Earthworms are more available during the summer months, during their breeding season. Brine shrimp are very tiny shrimp. They are extremely high in protein, so they should be used as treats rather than a regular part of your goldfish's diet. Identify frozen and freeze-dried dietary options for your goldfish. Frozen and freeze-dried foods often provide the same level of nutrients as live food. Frozen or freeze-dried foods are also good if you're a bit squeamish about handling live worms. The live food will most likely be available in frozen or freeze-dried form at your local pet store. Another advantage of frozen foods is that they are easy to store. If you have frozen crab, lobster, or mussels at home, you can also feed these to your goldfish. Make sure that they are cleaned and thawed before you put them in your goldfish's tank. Include fruits and vegetables in your goldfish's diet. Fruit and vegetables are important components of your goldfish's diet. They are a great source of nutrients and are low in fat. There are many types of fruits and vegetables that you can feed your goldfish, including peas, lettuce, broccoli, and apples. Whichever fruit or vegetable you choose, it will need to be softened, cut or diced, and peeled before you feed it to your goldfish. It will also be important not to season the fruits or vegetables in any way. Feed your goldfish small amounts multiple times a day. A good rule of thumb is to feed your goldfish no more than he can eat in about one to two minutes. Goldfish can literally eat themselves to death, so you need to be very careful that you do not need overfeed your goldfish. Feeding him up to three times a day should be sufficient. Grab just enough food that you can easily pinch between your thumb and index finger. This is about the amount of food that you should feed your goldfish. Know the proper way to prepare each type of food. With the many different types of goldfish food that are available, you will need to know the proper way to prepare each type of food. This will lessen the likelihood that your goldfish will experience digestive upset after eating. Pre-soak flakes to prevent your goldfish from swallowing air bubbles when he eats the flakes; swallowing air bubbles can lead to swim bladder problems and constipation. To pre-soak the flakes, dip them in the tank water a few times before fully placing them in the water. Feed them one to two times a week. Pre-soak pellets for 10 to 15 minutes, or until they are about twice their original size. Place a small amount of tank water in another container and place the pellets in this container. After they have softened up and increased in size, add them to the tank. Feed the pellets two to three times a week. Pre-soak freeze-dried food in a small container of tank water to prevent digestive upset. Completely thaw frozen foods before adding them to your goldfish's tank. Place the food in your refrigerator for the thawing process. Peel, chop, and soften fruits and vegetables. Boiling is a good way to soften vegetables. Fruits and vegetables can be given as occasional treats. Thoroughly rinse live food if you find it yourself in the environment. Rinsing earthworms with water will help to remove the dirt and potential disease-causing organisms that may be in the dirt. To feed worms, cut them into small pieces before putting them in your goldfish's tank; you could even try placing the small pieces on a toothpick and feeding them to your fish that way. Feed the live food once a week. Observe your fish when you feed him. Pay close attention to your goldfish when you feed him to make sure that he does not overeat. If he has eaten too much, his intestinal tract may become full of food, which would trap gas in his swim bladder and cause him to float aimlessly. If you see him floating like this, immediately remove any remaining food. Contact your veterinarian or local pet store for advice on how to treat a goldfish who has overeaten. Devise a feeding plan if you’ll be traveling. If you will be away from your house for more than a few days, make a plan as to how you want to have your goldfish fed. One option is to have someone feed your goldfish for you. If you choose this option, it would be a good idea to make a detailed list of your goldfish's diet with instructions on how to feed him while you are away. Preparing the foods ahead of time and placing them in individual containers may make it easier for whomever will feed your goldfish. Automatic fish feeders are also available. Visit your local pet store to learn more about these feeders. Keep in mind that goldfish can actually go a long time without eating. Although they will be hungry, goldfish can go up to three weeks without eating. Identify the location of your goldfish’s teeth. Goldfish do not have teeth in their jaws. Their teeth are located in the back of their throat, which allows them to crush food and swallow food whole. If you listen closely enough, you may actually be able to hear a crunching noise from your goldfish's teeth as he chews on his food. Learn about your goldfish's digestive system. Goldfish do not have stomachs. Instead, your goldfish's intestines do the digestive work that a stomach would normally do. In addition, the lack of a stomach means that your goldfish cannot eat much food at a time; the food that he can eat will move quickly through his digestive system.The lack of a stomach makes your goldfish more susceptible to digestive problems if he is not fed properly. Learn about the purpose of your goldfish's swim bladder. Your goldfish's swim bladder is an internal gas-filled organ that allows him to stay buoyant in the water. If not fed the proper diet, your goldfish can develop problems with his swim bladder, which means that he would not be able to easily stay afloat in the water. 
Learn what types of food your goldfish should eat. Include dry food in your goldfish's diet. Provide different types of live food for your goldfish. Identify frozen and freeze-dried dietary options for your goldfish. Include fruits and vegetables in your goldfish's diet. Feed your goldfish small amounts multiple times a day. Know the proper way to prepare each type of food. Observe your fish when you feed him. Devise a feeding plan if you’ll be traveling. Identify the location of your goldfish’s teeth. Learn about your goldfish's digestive system. Learn about the purpose of your goldfish's swim bladder. 