home Aquarium How many hours should the light in the aquarium be on

How many hours should the light in the aquarium be on

Optimal aquarium lighting times

The aquarium does not need constant lighting. The operating time of the backlight is selected individually, depending on the species of fish and plants, the arithmetic mean value is from 10 to 14 hours. The season plays an important role in determining the length of daylight hours, since in the autumn-winter period the daylight hours are shorter and this means that the regime should be adjusted.

How long should Aquarium lights be on?

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As already mentioned, plants need lighting to a greater extent. In order for the algae to develop properly, you should constantly monitor the operation of the lamps. If the daylight hours are longer than in natural conditions, algae will develop faster than necessary, water bloom and more rapid reproduction of harmful bacteria will begin in the reservoir, which will affect the behavior and health of its inhabitants.

Light sensors, alarms, or timers can be used to optimize daylight management. With these devices, the light will turn on and off at the specified time.

There are some rules that must be followed when using aquarium lighting.

  • The lighting in the aquarium must be turned on and off at the same time every day.
  • The transition from light to dark should be gradual.
  • The duration of the lamp operation over the seasons should be constant, but not more than 14 hours.

Who needs night illumination

Everyone makes a choice for himself whether the aquarium needs lighting at night. But before making a final decision, you should take into account the advice of experienced aquarists and the species composition of fish living in your home pond. Violation of the conditions for caring for pets can lead to diseases of animals and premature death.

For the inhabitants of the aquarium, the presence or absence of illumination at night does not really matter. When feeding fish, no lighting is required: they find food with the help of other senses. Plants also do not need constant lighting. The light in the tank should not be on around the clock. You can leave it at night if the aquarium is in a room without windows.

If the backlight works in the dark, then the aquarium should be darkened during the day.

There are several species of fish that are nocturnal. During the daytime, they mostly hide in shelters, behave sluggishly and unnaturally. If you breed such fish and still decide to use night lighting, then you should pay attention to the natural night lighting under the moonlight. It imitates the natural light of the moon and has a wonderful effect on the biological activity of plants and nocturnal fish species.

At night, as a rule, predatory fish, catfish, loaches and some others lead an active lifestyle. It is not recommended to keep day and night fish in the same aquarium, as they will experience the inconvenience of living together, and peaceful fish will suffer from predators.

Do I need to turn off the light in the aquarium at night and why it depends?

In order to bring the living conditions of fish and algae in an aquarium as close as possible to natural conditions, several important conditions will need to be fulfilled. One of them is lighting. Perhaps the population of the home reservoir does not really need it: fish and other inhabitants of the aquarium live at a depth under water, where sunlight does not penetrate. But if there are living plants, then you need to take a very responsible attitude to this issue.

Choosing the ideal lighting mode for your aquarium will require a lot of experimentation, observing the behavior of the inhabitants of the tank and the vegetation.

Is it possible to do without light at night?

In the natural habitat of fish, round-the-clock lighting does not exist. Many species of fish live underwater at great depths, where sunlight cannot get in any way. There are some groups in which development is inhibited from too long daylight hours.

Excessive light has a negative effect on the well-being of pets and other inhabitants of the aquarium. Without rest, the fish will be lethargic, lose their appetite, may start to get sick or show aggression towards neighbors.

The main species of exotic fish come from warm seas, the sun shines there brighter and longer than in our climatic conditions, but the light they receive during the day is quite enough for them. To understand if fish can do without lighting at night in an aquarium, you just need to imagine their natural habitat.

Living conditions that are as close to natural as possible allow the inhabitants of a freshwater reservoir to develop better, and their life expectancy will not decrease.

Nature has laid down the change of day and night, pets also need rest, so uncontrolled night lighting can interfere with them. From all that has been said, we can conclude that there are no significant arguments against turning off the light at night.

For information on how to correctly calculate the lighting in the aquarium, see the next video.

Illumination spectrum in the aquarium

The most demanding spectral illumination is underwater plants. In order for the processes of photosynthesis to take place in them, a violet-blue range of light and an orange-red range are required. This cannot be achieved with conventional fluorescent lamps. But modern LED and phytolamps do an excellent job with the task.

Light spectrum

Aquarium plants are especially demanding on the light spectrum. The fact is that successful photosynthesis of plants requires the presence of two narrow color ranges:

  • violet blue (about 440 nm);
  • and red-orange (approximately 660-700 nm).

It should be noted that standard fluorescent lamps do not provide sufficient Spectra illumination for plants. Modern fluorescent phytolamps allow you to fully organize the required spectrum. LED aquarium lighting (LED) can also be arranged.

How to calculate light in an aquarium?

Many aquarists advise setting the light intensity per liter of water. a 0.5 W lamp. In doing so, do not forget to take into account the depth of your aquarium: for fish living at depths, less light is needed than for shallow water.

As practice shows, you can experimentally choose the light in your aquarium, starting from the average 0.5 watts. If there is an excess of light in the aquarium, the water in it will begin to bloom, and the walls will be overgrown with algae. If there is insufficient light, it will be difficult for the fish to breathe, small-leaved plants in the aquarium will begin to die, and brown spots will appear on the walls.

Illumination mode

For comfortable conditions for keeping plants, you should create a twilight regime, which happens in the wild. This is the time when the sun sets slowly, typical of different climatic regions. Even tropical flora needs twilight. Too abrupt transition from light to dark causes stress in the seedlings. In living nature, the processes of illumination and darkness smoothly merge into each other. This must be taken into account when creating the lighting of home aquariums.

If the light is turned off and on abruptly, then the plants’ regime will change dramatically, they will not have time to adapt to new conditions and will change their appearance. Many species, even light-loving ones, need shading for a comfortable life. They often try to roll the leaves in bright light and get into the shadow of the aquarium. It should be remembered that harsh darkness is also dangerous. If nocturnal shade-loving species can survive the day in the shaded corners of the reservoir, then light-loving ones simply cannot develop in dark water. Therefore, it is necessary to consider a smooth transition from light to dark.

To create twilight conditions in the tank, you should turn on the room lighting before turning on the lamp. 15 minutes is enough for plants to move from darkness to daytime existence. For rooms with good natural light in the summer, this will not have to be done. When observing the aquarium at this time, you can see how some species of plants are activated at dusk. When the light appears, the bacopa begin to unfold the leaves and bloom.

The best kind of lighting for an aquarium is natural. If the container is next to the window, then the plants in such an aquarium look very beautiful due to the fact that they have enough natural light. But the natural illumination of the temperate climatic zone is not suitable for all types of flora. Tropical plants will definitely need an adjusted additional lighting. side or corner. The number of daylight hours for light-loving species is 11-12 hours.

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It must also be remembered that the sun does not always shine equally brightly. There are cloudy days, and the illumination then drops. When the sun’s light is too bright, that’s not good either. The water heats up in the sun and the plants feel uncomfortable. In the strong light of the sun, the water in the aquarium can bloom, the plants will begin to grow strongly, taking away free space from the fish. In the evening, sunlight will also not be enough to illuminate the aquarium.

It is necessary to regulate natural lighting using artificial lamps. It must be remembered that the bulk of the light into the artificial reservoir must fall through the top. With the correct alternation of natural and artificial lighting of the tank, you can create comfortable conditions for both fish and aquatic plants.

Consequences of improper illumination

For an aquarium where different types of plants live, a light period of 10-12 hours a day is suitable. Plants need a change of day and night, but in some reservoirs, the period of illumination is artificially increased in an effort to accelerate the growth of flora. The natural alternation of day and night helps regulate the life rhythms of living plants. With too long or short lighting, they become stressed, the regime changes and diseases can develop.

The difficulty is that some aquarium plants need a lot of light to develop, but this can harm the fish, as most aquarium fish species are used to living in shaded areas of the reservoir (in the wild). Too long and too bright lighting affects the appearance of the inhabitants of the aquarium. Fish can turn pale, lose their brightness and hide from light.

Problems with improper aquarium illumination occur in non-standard containers, the height of which is more than 38 cm. In tall tanks, plants growing on the ground lack light. Sometimes they try to solve this difficulty due to the intensity and duration of artificial illumination. The desire to improve the conditions for low-growing soil seedlings leads to mistakes. Too bright lighting adversely affects the fish and the microclimate of the reservoir. The inhabitants of such an aquarium are inactive, as they constantly need protection from bright light. Fish tend to hide from bright light, so the aquascape seems to be uninhabited. In such conditions, diseases often appear, and water begins to bloom.

Watch a video story about lighting in the aquarium.

Duration of aquatic lighting and options for ease of control

500 rubles), unlike mechanical timers, they do not go astray when disconnected and power surges, which is important!!

Should you turn off the lights in the aquarium? Light timer

Despite the fact that the fish living in the aquarium are designed to entertain and pacify their owner with their external appearance, do not forget that they are living creatures living according to the laws of nature. Let’s remember that fish in natural conditions live in water, rivers, ponds and other bodies of water. Of course, we all understand that at the bottom of a natural reservoir it simply cannot be as light and bright as in a backlit aquarium.

By and large, the fish do not need light directly at all. Light is only needed for two purposes:

Firstly, thanks to the backlight, you can contemplate your pet;

Secondly, if there are living plants in the aquarium, they need light in order for the plants to have the process of photosynthesis.

In nature, also around the clock, light does not penetrate the water column and does not continuously illuminate the bottom. Therefore, having a backlight, you must also purchase a light timer in the aquarium. After all, there is no need to leave the lamp on at night. In order not to forget to carry out the change of day and night, a timer is also suitable.

For fish, by and large, it does not matter whether there is light in the aquarium or not, it is most important for them that there is a comfortable temperature near the water in which they live and there is always food for feeding. The purity of water directly for fish is also one of the first places and occupies a major position than the presence or absence of artificial lighting.

In addition, the light can be turned off not only at night but also during the day. You just need to imagine how lighting occurs in nature. After all, the sun does not shine continuously. Sometimes it is obscured by clouds or just inclement weather. So the backlight can only be turned on for a few hours a day. Based on the above, it can be noted that the question of whether to turn off the lights in the aquarium is very simple and clear.

Turning off the light is not only possible but also necessary, you should not illuminate it continuously throughout the day and all night. In addition, a careful attitude to electricity consumption will have a pleasant effect on changing bills for electricity at the end of the month.

Even when using energy-saving lamps with their round-the-clock operation, you can also get an impressive figure in a month. In order to prolong life in the aquarium, it is necessary to adhere to the conditions of keeping the fish as long as possible, bringing them as close as possible to natural conditions.

How long to illuminate the aquarium. the rules for calculating the duration of lighting and daylight hours.

Proper aquarium lighting has been a longstanding subject of heated debate and controversy even among seasoned aquarists. The most commonly discussed are the best light sources, their spectrum and power.

In this article, let’s look at another important aspect, namely the duration of the lighting.

How long should the light in the aquarium be on so that the plants and fish in it develop as in their natural environment, feel at home and nothing will disturb them??

Most of the aquarium plants are native to the tropical regions of our planet. And there the duration of daylight hours does not depend on the time of year and is approximately always the same. about 12 hours.

If we also take into account the refractive index of the light flux in water, then the normal illumination in natural reservoirs does not exceed 10 hours at all.

It is this length of daylight that is favorable for most plants.

If you break it, then expect the rapid growth of algae. What is the reason?

In all normal tropical plants, photosynthesis after 12 hours of continuous light decreases, but in algae, which are more related to a temperate climate, it does not.

As a result, their natural rivals disappear and they begin to absorb all nutrients alone, without any competition. Hence their excessive growth and flowering.

However, in addition, the length of daylight hours in the aquarium depends on 3 main factors:

For example, for fluorescent lamps it will be 10-12 hours, and for metal halide lamps it will only take 6-8 hours.

The same short time is suitable for aquariums where there are no rich plants, and mainly fish, pebbles or driftwood live for decoration.

At the same time, for fish, you can turn on and off the light absolutely at any time. They do not have to follow any particular regime. The most important thing is that it is dark for a given period of time.

For example, you have CO2 naturally enters the water through the open top. There is no forced filing, and therefore there is often a lack of it.

What does this lead to and how does this relate to the duration of the lighting? With a lack of carbon dioxide, plants begin to produce phosphates stored for this case.

And this, in turn, leads to a rapid bloom of algae. Therefore, it is highly desirable for you to know how many hours of illumination the CO2 contained in the water is depleted to a minimum. On this and end the highlight, taking a break.

Once the CO2 is restored to normal levels, the luminaires can be restarted. Take such measurements once and stick to the schedule in the future.

Determine the concentration of carbon dioxide using aqua testers and indicator liquids.

When fertilizers are applied strictly according to the dosed portion calculated by the manufacturer, then the daylight hours for the normal absorption of all elements can increase, from the calculated 8-10 hours to 11 hours.

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Otherwise, some of the nutrients will simply clog the jar, not absorbing in any way and not affecting the growth of greenery.

As you can see, these influencing factors can significantly change the time, therefore the intensity and duration of daylight hours is selected for each aquarium individually.

It is very convenient in this matter to initially navigate by the long stem.

For example, you have no idea even the approximate lighting time. Turn on the light in the morning and watch.

As soon as the crown of the plants begins to flatten and the leaves close. this is a signal to go to bed and dim the lights. You write down this actual time and then use it, and not the advice of theoreticians from the Internet.

HOW LONG SHOULD YOU KEEP YOUR LIGHTS ON? | DAILY TRIM 24

At the same time, it is not necessary to turn off the light immediately, but after about an hour, one and a half.

Nevertheless, even without practical experience and observations, there are several rules and regulations that must be followed when choosing the duration of the aquarium lighting.

As we found out earlier, the total lighting time should not exceed 11-12 hours a day. At the same time, too short intervals have negative consequences.

When is the best time to use this time, day or night? Aquarists do not recommend illuminating plants at night in complete darkness. It is better to do it during the daytime.

The fact is that natural light during the day is present in your room anyway. As a result, artificial night illumination 10 hours will be redundant in combination with natural light in the morning and at lunchtime.

So, again you can say “hello” to algae.

Now let’s touch on the issue of intensity and brightness of lighting. How to choose the right power and the number of lamps of different designs, from simple or fluorescent to LED, is described in detail in the article below.

Briefly in terms of brightness, we can say that for a slow herbalist, 40 lumens are enough for each liter of water in a container. For a forced herbalist. 60 Lm / liter.

After you have chosen the lamp you like and decided on the time of its operation, it is not recommended to turn it on immediately at full power. Plants need to get used to it.

Therefore, using a dimmer, you need to make sure that the bulbs at the very beginning shine a maximum of 2/3 of their peak. Continue this inadequate lighting for about 1 week and observe the plants closely.

If everything grows and develops normally, then you can add a little brightness and continue observing. If the front wall of the aquarium begins to quickly overgrow and turn green, this is the first sign of an overabundance of light.

In this case, decrease the power by one step.

But what if you don’t have a dimmer and have nothing to artificially adjust the brightness and intensity of the lighting with? In this case, you will have to gradually reduce the duration of daylight hours from the original calculated.

There is another option. just raise the lamp a little higher.

Select the height experimentally according to the results of observations of the front wall. It shouldn’t overgrow quickly.

Also, do not forget that direct sunlight should not enter the aquarium. The bright sun can not only illuminate, but also heat the water.

Which, again, will not please all representatives of flora and fauna.

Our temperate climate and direct sunlight are not suitable for all types of greenery. Especially tropical representatives.

Some instances may even require side or corner lighting.

Based on this, place the aquarium near the side wall from the window, in the far corner of the room, or build it into niches away from the direct sun.

This will help to dose the light in the proportion you originally intended. There will be no errors and the influence of natural light.

You can also make step lighting.

That is, part of the lamps or one channel of the lamp shines for the entire duration of the daylight hours, for example, 9 hours. And another channel or another part of the lamps turns on only 2 hours after starting the first.

Then they shine together for 5 hours. 2 hours before the light is completely turned off, some of the lamps go out again, and the rest burn out until the very end of the day.

This simulates the natural peaks of maximum lighting in the aquarium.

The same can be done by a special controller with the ability to simulate sunrise and sunset. True, it displays the illumination at full power smoothly and gradually, and not stepwise.

Cutting off the lights can be stressful for young seedlings. And they have not adapted to such conditions, they will begin to change their original color.

The same applies to the sudden appearance of light after a night break. For example, in winter, when it is still dark outside the window early in the morning, you should not immediately turn on the aquarium lamps to full.

In the summer, such a procedure does not need to be done.

Some people take a break from daylight hours to combat algae formation. Let’s say your total daylight hours are 10 hours.

In the morning you turn on the light for 5 hours, and then the timer turns it off for 4 hours. Then the light is restarted for the remaining time.

There should be weak sunlight in the room from a window, or from a chandelier or sconce. In the natural environment of the tropical zone, such blackouts do often occur during a thunderstorm.

And most plants are no stranger to it. But algae for some reason do not like this and their growth is noticeably reduced.

It is also useful from an aesthetic point of view. In the evening, coming home from work, you can fully enjoy the beautiful view of floating fish and green plants.

If you do not take a break, then after turning on in the morning at 7.00 and leaving for work, your aquarium, according to the previously given recommendations, should be turned off at about 18.00. So it turns out that you will spend the whole evening near a dark container with water, never enjoying the results of your labor.

Therefore, such a break, in addition to fighting algae, is a very useful thing and a delight for the eyes.

In addition, as experiments have shown, when organizing pauses in lighting, the release of CO2 increases in the dark phase.

Accordingly, you will no longer have a pronounced carbon dioxide starvation, and sharp changes in the CO2 content in the aquarium.

All this can be done with inexpensive and easily accessible timer sockets.

And if you are leaving for a few days on vacation and you don’t have a timer? Then try to add natural light to the room as much as possible. Part the curtains or blinds.

Nothing bad will happen if the fish and plants are exposed to natural light for several days. At least it will be much better than leaving the lamp on 24/7.

If, despite all the recommendations, you still have an outbreak of algae growth, then you must first of all find out the cause of their appearance and eliminate it.

In many cases, a decrease in the intensity of illumination and a reduction in daylight hours once by 2-3 hours helps here. After the algae is gone, you can experimentally find out the required duration by adding time for several days for 30 minutes.

Aquarium lighting time rate

The following information will help to determine how many hours the light should be on in an aquarium with plants, when the lights should be turned on and off.

There are several options for calculating the rate of lighting an aquarium. The main parameters to consider:

  • the volume of the aquarium, its depth,
  • species of fish and plants,
  • bulbs used for lighting,
  • water (fresh or sea).

Calculation according to the formulas does not give one hundred percent guarantee of the correctness of the lighting, which can only be verified with time empirically.

When using fluorescent lamps, the illumination is calculated from 0.3 watts per liter of water in the aquarium, taking into account the following information:

  • moderate illumination: 0.2-0.4 W / liter. in the presence of shade-loving fish (nocturnal, for example) and plants (Cryptocorynes, Vallisneria, Javanese moss, some Echinodorus);
  • average: 0.4-0.5 watts / liter. if the number of plants in the aquarium is limited;
  • high: 0.5-0.8 watts / liter. in 90% of cases suitable for lighting an aquarium with plants;
  • high: 0.8-1 Watt / liter. an indicator that should be at a dense planting.
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Another important parameter to consider is that in water the light intensity decreases by about 50% every 10 cm.At the bottom of the aquarium, the illumination should not be lower than 60 Lx.

Interesting! Illumination. the ratio of the luminous flux to its area. The unit of measurement is lux. Lux = lumen / m².

Luminous flux is a quantity that characterizes the emission of luminous intensity per unit area. Measured in lumens.

Luminous efficiency is the ratio of the luminous flux to the power consumed by it. Measured in Lumen / Watt.

The luminous efficiency of fluorescent lamps is two to three times higher than that of incandescent lamps, and that of LED lamps is 7 times higher.

The main value when choosing the type and number of bulbs is the suites, information on which can be found on the bulbs themselves. The average for not very large and sparsely planted aquariums is 3000-4000 Lx. From 1000 to 10000 Lx. an indicator sufficient for plant photosynthesis. But there is also a dependence on the depth of their growth. So, for narrow-leaved Cryptocoryne, 400 lux is enough.

It must be remembered that different fish and plants have different lighting requirements.

There is another opinion about the required illumination. Takashi Amano. aquarium designer, creator of a new direction in the design of freshwater aquariums. “Natural Aquarium” claims that the importance of water surface area is important.

The calculation can also be based on lumens. So, at a low level of illumination, the indicator is 15-25 Lm / l, with an average. 25-50 Lm / l, with a high level. 50 Lm / l.

The power of different types of lamps and their luminous flux are shown in the table below.

Kaspar Horst recommends calculating the illumination based on 30-50 lm per liter of the volume of the aquarium (by external dimensions).

And finally, the dependence of lighting on water. If the aquarium is with sea water, then you need to use more of the blue spectrum of light (in addition to the main lighting), and if with a fresh one, then the ratio of red Spectra to blue is 5: 1.

How much light should burn in the aquarium

Proper aquarium lighting is the key to the health and beauty of its inhabitants.

A variety of light bulbs, a wide selection of designs for lighting and backlighting (including programmable electronic ones) allows you to solve the problem with light competently, efficiently and at the lowest cost.

A properly selected lamp will not only provide comfort to the inhabitants of the aquarium, but also get aesthetic pleasure for its owner.

Herbalist Step Lighting

With the step lighting method, the light intensity rises to a peak and then gradually decreases.

The method allows you to simulate the natural length of daylight hours in an aquarium and is distinguished by its effectiveness, and also helps to significantly reduce (up to cessation) the growth of algae.

How much light should burn in the aquarium with the stepwise method?

In practice, step lighting is implemented as follows. Some of the lamps used shine all day, others. a couple of hours. For example, with a daylight day organized for the inhabitants of the aquarium at 9 o’clock, the first two hours only some lamps light, then the remaining ones turn on for 5 hours. After that, for the remaining two hours, the same lamps are shining as in the morning. The peak brightness of the light should not exceed the specified 5 hours.

To reduce the growth of algae at the initial stage of creating an aquarium, it is recommended to use a ratio of 3: 3: 3, that is, 3 hours in the morning and evening. lower light, and 3 hours. peak light. After a month, you can switch to the 3: 4: 3 mode and stick to it in the future.

Consideration should be given to the type of aquarium plants. So, if they are slow-growing, then the mode will be 4: 2; 4, and if they are more demanding and / or fast-growing. 3: 4: 3. By the way, there is a special controller that will eliminate the need for constant manual on / off switching.

Tip: In winter, before turning on the light in the aquarium, it is better to turn on the light in the room first. This way, the fish will not experience stress from harsh strong lighting.

Calculation and minimum time

When determining the minimum backlight time required for normal growth and development of the aquarium dwellers, observation is the best solution. The light turns on at any convenient time. During the day, you need to observe the plants. when the plants “fold” the leaves, it means getting ready for bed. After about an hour, the lights can be turned off.

If you want to watch the inhabitants of the aquarium in the evening, you should turn on the light, for example, at 10-12 hours. Then the shutdown time will be 20-22 hours.

Do not light the aquarium constantly in order to avoid the risk of diseases of fish and plants, as well as the formation of algae and “bloom” of water.

Natural light and aquarium installation location

There is a misconception that by placing the aquarium on the windowsill, the best lighting conditions are provided. However, the possible negative consequences of this decision:

  • in summer the water in the aquarium will be very hot,
  • natural light promotes active reproduction of green algae.
  • light passing through the water column and the glass of the window and aquarium loses its intensity.

Duration of natural light should not exceed two hours.

It is best to set up the aquarium on the opposite side from the window. It is important to limit access to direct sunlight.

How lighting affects CO2

Photosynthesis of aquarium plants does not depend on the concentration of CO2, but on the lighting. Plants use light energy to convert water, CO2 and nutrients into tissues. In the absence of the required level of lighting, CO2 and nutrients are unclaimed, since photosynthesis does not occur.

A sign of photosynthesis is the formation of oxygen bubbles on the leaves of plants, which are covered with them a couple of hours after turning on the light. This indicator is a visual sign that the condition of the aquarium is good and the lighting is organized correctly.

An important aspect of caring for your aquarium dwellers is controlling oxygen saturation. So, at the beginning of daylight hours, oxygen saturation should be from 5 mg / l, and at the end. 8-10 mg / l. Compliance with these indicators indicates that the lighting is organized correctly.

Do you need light in the aquarium at night

An important question is whether you need to turn off the lights in the aquarium at night. There are two opposite points of view on this question. The first one suggests that natural reservoirs are illuminated by the moon at night, and, therefore, a night illumination of the aquarium is needed (namely, at night, weaker, and not the one that is used during the day). And the second is that the aquarium does not need light at night.

Night lighting is not required for fish and plants, but rather for the owner for aesthetic reasons and out of interest to observe the nightlife of the aquarium fish. In view of the above, you can use a faint blue backlight to simulate the light of the moon.

But in any case, the main light must be turned off at night.