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Does Fish Food Expire? Everything You Need To Know!

The number of people starting out in the fish keeping hobby is higher than ever right now and we have noticed more and more questions being asked from beginners month in and month out about caring for their fish.

One thing that we have seen people asking about is if fish food expires or not and due to this topic causing some confusion with a lot of contradictory information on social media about fish food expiring, we have decided to publish this article.

All types of fish food will eventually expire and although there are certain things that you are able to do to some types of fish food to make it last for as long as possible, all fish food does have a maximum shelf life.

Once the fish food gets close to or passes its expiration date, it should not be fed to your fish due to the nutritional profile of the food rapidly dropping off.

With there being so many different types of fish food on the market as well as different types of fish food having their own maximum shelflife as well as different ways that you are able to preserve the food, we wanted to publish this dedicated article on the topic to try and help as many of our readers as possible.

Does Fish Food Expire?

All types of fish food will eventually expire with the calorie and nutritional content of the food eventually dropping off to a level where the fish food is essentially useless.

Some types of fish food can end up presenting a potentially serious health risk to your fish once it has expired too so you really do have to try and avoid feeding your fish expired fish food if possible.

There are five main types of fish food that people use within the fish keeping hobby as shown below:-

  • Flake Fish Food
  • Pellet Fish Food
  • Live Fish Food
  • Freeze Dried Fish Food
  • Frozen Fish Food

In this article, we will be taking a look at each of these in more detail to go over how you can tell if the fish food has expired, the risks of using the food when expired, and how long of a shelf life you can expect from these foods.

Do Fish Food Flakes Expire?

Fish food flakes are usually the most commonly used type of fish food within the fish keeping hobby and when stored correctly, they can usually last the longest without its nutritional profile degrading.

The issue is, due to its flake based nature, even a small amount of moisture in the food is able to “melt” the flakes into each other and quickly start problems in the food.

Depending on the exact type of fish flake food you get, you can sometimes expect a maximum shelf life of around three years before it expires and its nutritional profile starts to fade.

If moisture does manage to get into flake based fish food then you will commonly start to see the food become unsuitable for your fish far sooner than it otherwise would have.

This is why proper storage is key for flake based fish food and you have to keep it in a dry place with low levels of humidity to make sure that the food is able to last for as long as possible.

The use by date on your fish flake food will give you a good idea of the expected expiry date for the fish food but you can usually see the color of the flakes fade rapidly as it gets older and becomes less nutritional.

Does Pellet Fish Food Expire?

Pellet based fish food tends to be the second most commonly used type of fish food within the hobby and depending on the specific pellet formula you get, it can last for a very long time with ease.

Unlike fish flake food, fish pellet food tends to do much better with moisture too removing this potential risk from the food helping to make sure that it will hold its nutritional value and be a suitable food for your fish for as long as possible.

Most fish pellet food products will have a shelf life of between three and give years but it is unlikely that you will not use all of the pellets up when feeding your fish within this time.

Depending on your situation, the long shelf life of pellet food does offer the advantage of people who keep large numbers of fish being able to bulk buy their pellet food to keep their costs as low as possible though.

Most pellet foods tend to turn to a very pale white color as they get close to their expiry date with this being a clear indication that the fish pellet food is either close to expiring or has already expired.

Does Live Fish Food Expire?

Live food is becoming more and more popular due to it being so cheap and easy to order online right now allowing people to get fresh supplies of popular live food options such as bloodworms, daphnia, and brine shrimp sent to their homes.

Although fish really do seem to love eating live food, it does have the downside of most live foods having to be used within a week of ordering them.


Even then, the nutritional value of the live food can rapidly drop off after a couple of days even if you do add a food source to their storage container.

In most cases, you can usually tell if there live food is close to expiring as the color of the food will fade rapidly and you will usually notice dead worms and shrimp in the container too.

Live food is a great option for fish but in our opinion, you really should just be going with a brine shrimp hatchery if possible as they are only around $20.

These hatcheries allow you to quickly and easily hatch your own brine shrimp at home as required to offer your fish live food when needed without having so many that they will expire as a food source and have their nutritional profile deplete.


Although it is often not referred to as “live feeding” some omnivore and herbivore fish species will eat large amounts of algae and detritus in your tank.

This can be a great way to offer your fish a fresh food source that can technically last for ever in the right tank setup due to the algae or plants just continuing to grow.

We would always recommend that you consider adding live plants to your aquarium if possible due to the benefits they offer with your tank’s ammonia cycle, oxygen levels, and sight breaks for your fish to hide but they can also be a great food source too.

Does Freeze Dried Fish Food Expire?

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With more and more people within the fish keeping hobby realizing that freeze fried fish food actually has a higher nutritional profile than live food, it is becoming a more and more popular option.

Not only is freeze fried fish food often cheaper than many other types of food but it can also last longer before it expires while also often having the best nutritional profile available.

In addition to that, you also have the options of freeze dried bloodworms, freeze dried brine shrimp, and freeze dried krill offering some great veriety for your fish food too.

Due to being freeze dried, these foods don’t do well with moisture so they usually have to be stored in a cool, dark, dry place to make sure that they are able to last for as long as possible.

In most cases though, when stored correctly, they are able to last indefinitely while also holding their nutritional value long past their use by date on the packaging of the food.

As they age, freeze dried fish food will often break into smaller pieces but this is usually not an issue for smaller fish species as they will happily eat the broken freeze dried insects without issue anyway.

Does Frozen Fish Food Expire?

Frozen fish food will technically not expire provided that it is kept in its frozen state while also holding its nutritional value for a very long time.

The issue is that if frozen fish food is defrosted then it usually has to be fed to your fish within a 24 hour time period due to the freezing process damaging the cells of the food causing it to go bad very quickly.

If you don’t think that you will be able to keep the frozen food in its frozen state indefinatley then we would usually recommend that you go with the freeze dried variant instead if possible.

In most cases, the nutritional value is very similar between freeze dried and frozen fish food anyway but frozen fish food can often be more expensive.

Due to this, we would usually just recommend that our readers go with a decent freeze dried fish food instead of an actually frozen fish food if possible.

Can Fish Eat Expired Fish Food?

Technically, fish can eat most types of expired fish food with minimal risk but the issue is, expired fish food usually offers little to no nutrients to your fish.

This can then cause knock end effects later down the line due to a lack of calories, vitamins, and minerals in the diet of your fish.

Live food can often have problems with disease or parasites once expired so we wouldn’t recommend that you use this fish food type once it is more than a week old.

Although frozen fish food technically has a use before date after it is defrosted rather than a date from the time of purchase, the labeling can be difficult to understand.

In our opinion, any frozen fish food that has been defrosted should be feed to your fish within 24 hours of being defrosted and then you should class it as expired.

Once defrosted frozen fish food has past this date it should not be given to your fish and you should throw it away.

Is Expired Fish Food Poisoning Real?

Expired fish food poisoning is a real issue and it is far more common with live and frozen fish food than with flakes, pellets, and freeze dried fish food.

Still, expired fish food poisoning can technically happen with all types of expired fish food presenting a risk to your fish.

Thankfully, modern fish foods usually have a use by date that is so far in the future after purchasing that it is very rare that our readers will actually end up having issues with their fish food expiring anyway.

Does Expired Fish Food Sink Or Float?

You will often see people on social media claim that you can tell if your fish food has expired because it will instantly sink but this is not correct and this method can’t be relied upon.

Firstly, not all fish food floats anyway or sinks anyway and there are various products on the market that have been designed to float indefinitely or sink quickly to make it easier to feed certain species of fish.

Even once these fish foods have expired, they will still usually float or sink as designed due to the excess air in the food causing it to float or the tightly compact pellets removing all air forcing them to sink.

We just wanted to include this in our artice as we have lost count of the number of times we have seen people saying that this is a way to tell if your fish food has expired on social media but it is not correct.