Feeding tropical fish 1 – 3 times a day is enough. However, you should be careful of feeding only a small amount every time. Provide only that much food that your fishes can complete eating within a minute or two, any excess food can cause digestive problems, lead to pollution of aquarium water, and can even cause fish death. So, if there is any excess food left behind after five minutes, you should use a scoop to get that out.
How to Know What Is the Right Amount
The best way to understand how much you need to feed will be to observe the fishes at regular intervals while feeding You can add small amounts of food at a time, and if all the foods get eaten in few minutes, then you can add some more. If food is not eaten within 5 minutes, they will not be eating it at all. Not eating, at times, can be a sign of illness or larger or aggressive fishes preventing the other fishes from eating, so be watchful.
You should not add food based on the size of the tank, instead offer food depending on the number of inhabitants. While dropping food spread it all over the surface of the water, so that more fishes can eat together at the same time.
Different Types of Food for Tropical Fish!
Just knowing how much to feed is not enough, you also need to feed the right foods for your fish to get the best nutrition possible.
Flake Foods
Flake food is amongst the most popular type of food used to feed tropical fishes. It is perfect both for medium and small fishes, including the general community breeds like livebearers, barbs, and tetras
. There are many manufacturers producing flake foods, so you have a wide variation and brands to choose from. It will be best to opt for fish flake food from some reputable manufacturer, but also try to provide some variety in diet by opting for different flake types and brands, and choosing other type of fish food mentioned below.
Various colour enhancing flakes are available so you can also opt for them to boost the natural colour of your fishes. We highly recommend Omega One! It breaks down in the tank slower than others so it wont cloud your tank. It enhances your fishes colours. Its packed to the brim with nutrition your fishes crave. And your fish will love it! Various manufacturers even offer variations like veggie formulas for the herbivorous fishes.
Pellet and Granular foods
Micro-pellet and granulated fish foods are also very popular. These are a great alternative to flake food, and thus help you bring variety in diet. Many such foods easily sink through the water, and thus are perfect for bottom-feeding or midwater fish. Pellet and granular foods are also a great option for autofeeders, as they are very less chances of it clogging compared to flake foods.
Tablet and Wafer Food
Tablet and large wafer disc foods are perfect for bottom-feeding fish. They easily drop through the water, and are generally too large for the smaller fishes to swallow completely, thus allowing bottom-feed fishes like loaches and catfish to feed on them. These foods are also perfect for various suckermouth catfish that scrape at food’s surfaces. Tablet and wafer food allow such fishes to take their food in small amounts over longer time, just as they would in their natural habitat. Some types of tablet food can be pressed against your aquarium’s glass wall, so that the fishes can see them easily and thus feed on them.
Sticks and Floating Pellets
Floating pellets and larger food sticks are perfect for large fishes like many cichlids. These foods serve as a substantial diet that will not get lost in the filter intake, substrate etc, as fast as finer foods. Many manufacturers produce pellets and sticks for carnivores or herbivores. As far as omnivores are concerned, you can rotate both these types of food.
Freeze-Dried Foods
Freeze-dried foods allow you to feed your fishes natural foods like bloodworm and tubifex that is safer for them than live foods, and usually a better option than frozen foods. Foods like freeze-dried bloodworm will float, and thus are a perfect option for those fishes that feed near the surface, like African butterfly fish, hatchet fish, and gouramis. Freeze-dried tubifex is created in a cube shape that you can press against your aquarium’s wall, helping your fish to eat in full view.
Frozen Foods
Frozen foods are great option for many tropical fishes, and perfect for those fishes that do not take dry food readily. You can get such foods in wide variety. Some are good for babies or smaller fishes, and includes baby brine shrimp, daphnia, and Cyclops. Others foods like white mosquito larvae, black mosquito larvae, krill, bloodworm, adult brine shrimp, mysis, and veggie formulae and so on are ideal for medium-sized fishes.
Live Foods
Though live foods are not so popular nowadays, owing to the availability of so many types of nutritious fish foods, yet many fish owners prefer feeding them as occasional treats, and many fishes actually like the “wriggle factor” of such foods. It can also be a great option for some wild-caught fishes that are taking time to get used to aquarium foods. The most commonly available live foods are daphnia, shrimp, brine, and bloodworm.
Veg Household Food
Various household vegetables can be used for feeding the omnivorous & herbivores in your tank. Many fish keepers offer Suckermouth catfish veggies like cucumber, potato, fish etc. These can be kept in the tank overnight, so that the fishes can nibble on them, and then removed the next morning.
Fry Foods
Various types of food are particularly available to feed baby and fry fish. These can be liquid suspension foods or fine powder formulations. They are useful during the early stages, and are very good for development and healthy growth of baby fishes. You should feed such foods more frequently but in very small amounts. 
Several times every day would be perfect, but remember that you will need additional water change to keep the quality of water high.
You may even culture live foods yourself for the baby fishes. Live foods are a good option for those fishes that do not easily take prepared foods. Moreover, this will be a great economical option for you if you have to feed a large number of fishes. The two most popularly cultured varieties for this purpose are microworms and baby brine shrimp.
These are some of the best foods for feeding tropical fish. As already mentioned, there are many brands offering different varieties of foods, so make sure you do experiment with the different available options. Also, make sure to feed the right amount, feeding more than needed can prove to be bad, even fatal for your tropical fishes.