Can Fish See In The Dark To Eat? – Detailed Answer

Having a sufficient diet plays a vital role in ensuring your fish’s well-being. That said, numerous factors can affect the efficiency of your feeding habits. For example, when to feed your fish is of utmost importance, since timing can determine how much your fish want to take in.

So, can fish see in the dark to eat? Is it okay for aquarists to feed their fish at night? The answer lies in the article below!

Can Fish See In The Dark To Eat?

Yes, most fish can see in the dark to eat, or at least they could make out enough of what is going on to adjust their movements.

fish swimming in tank

That said, you should know that the night vision of fish is not exactly the best compared to other animals. At night, they prefer using their sense of sound and smell to detect food coming in.

Furthermore, fish use their lateral line system to determine whether there has been a pressure change in the tank’s water.

When combined, these features help fish successfully locate the amount and type of food being thrown inside the aquarium. Hence, it does not necessarily matter if you feed your fish at night or in the dark or not. Either way, they will still be able to eat.

Do Aquarium Fish Need Darkness?

Yes. All aquarium fish need darkness, as darkness helps develop a fixed routine for these aquatic animals. Remember, all of your fish have grown accustomed to having a day-night cycle. Hence, lacking darkness may confuse your fish and prevent them from behaving normally.

In most cases, aquarists create darkness for their tank by turning off the aquarium light for at least 10 to 12 hours per day.

However, if you do not have one at your disposal, feel free to place the tank somewhere near a natural source of light. When the night comes, simply cover it with a blanket or a covering. This way, you can still create a day-night cycle for your fish without costing a lot of money.

Can Fish See Food In The Dark?

Yes and no. Technically, fish do have night vision that allows them a certain degree of orientation when left in the dark. But still, most of them do not rely on their eyes to see food in the dark.

Rather, they use their sense of smell and sound to detect where and when food is coming in. Furthermore, fish are equipped with a lateral line system, acting as a combination of sensory organs that locate vibrations and movement in the water.

Admittedly, fish cannot see food in the dark. That does not mean they fail to consume food when it is time to be fed. And of course, fish in the wild still have to eat at night rather frequently, so rest assured that your fish will be fine.

Do Fish Like The Dark?

Most of the fish you are familiar with do not like the dark as much as they need it. First off, darkness provides nighttime for fish to rest and relax. When the environment is brightly lit, chances are they will not be able to stay calm in one place.

Hence, sleeping becomes something that fish can only do during darkness.

Secondly, not all fish enjoy swimming around enthusiastically all the time. Some species are particularly skittish and shy compared to others, which means they need somewhere to hide occasionally.

Darkness offers the perfect opportunity for fish to seek refuge and protection against others inside the tank. Hence, it is of utmost importance that these fish have the night backing them up when looking for a hiding spot.

Still, you may find that some fish are particularly active during the night. They are known as nocturnal fish, which are more alert and likely to move around in the dark.

These include gobies, angelfish, wrasses, and puffers. If you happen to nurture these species inside your aquarium, then you must provide them with a certain level of darkness to accommodate their needs.

What Do Aquarium Fish Do At Night?

Fish’s activities at night vary significantly based on their species.

Most aquatic animals take advantage of the night to sleep and rest. Some choose to lay directly on the substrate while others hover near the water’s surface.

These animals believe that darkness acts as the ultimate protective layer, which allows them to lower their guard and regain their energy through resting.

On the other hand, some fish become particularly energetic when night comes. These fish will swim around looking for food and companions. They even prefer to mate and interact with others in the dark without having much difficulty.

What Happens If You Leave A Fish In The Dark?

fish in the dark

Although fish do need darkness, leaving a fish in the dark for too long is not good for them. In this case, being exposed to darkness for an extended period will cause the fish’s skin to fade. Naturally, they will lose their vibrant and colorful skin shades due to a lack of sunlight.

Another consequence of being left in the dark for too long is that your fish will gradually grow sluggish. As they cannot determine when it is daytime, they end up sleeping and resting way too much and fail to exercise regularly.

In the long run, being left in the dark can be detrimental to your fish’s survival.


Can fish see in the dark to eat? Yes, they totally can! Thus, feel free to feed your fish at night if you cannot find the time to do so during the day. And if you find these tips and tricks helpful, make sure to spread the word to other aquarists!