Light helps plants in the aquarium to prepare their food themselves and thrive. For all this, the duration of it holds a lot of significance. 

How Long to Keep Aquarium Lights on For Plants? An optimum supply of light is necessary for aquarium plants. The schedule of light relies on the plant type, their need, and brightness level. In General, aquarium plants need between 8 to12 hours of light.

Sometimes, this light raises the temperature of the water, which can harm the plant’s nourishment. While lighting your aquarium, you must keep an eye on the heat generated due to light.

How Long to Keep Aquarium Lights on For Plants?

Excessive light in an aquarium can lead to a rise in algal growth that reduces natural beauty. It affects the nourishment of plant and animal species in the aquarium.

This light must optimize by room or ambient light. If the light present is enough for your aquarium, then rely on this light and do not go for additional light at all.

For a proper schedule, you can maintain and determine the light timing. You have to figure out the appropriate duration and use a timer that monitors it.

With this, you can turn it ON and OFF during day and night time. Sometimes any issue appears even after the proper schedule, so decrease timing from 1 to 2 hours.

If the fish tank has no plants, they require less light. You can buy the on-off timer and connect it to the light unit. It provides the desired period of light.

Most of the lights come with a dimmer, so you can change their brightness according to need, which fulfill their needs. For best plant nourishment, consistency is the essential component. 

Optimize aquarium light keeping in view photosynthesis needs of plants

All plant species prepare their food by themselves. For this, they need sufficient light along with carbon dioxide and water.

It provides nutrients to aquatic species, and oxygen releases during this process, that utilize by animals for breathing and breaking food molecules.

For this, you must keep the light duration as long as the average of a single day that may be around 8-12 hours a day.

Adjust daylight with the additional light in the day time

While deciding the duration of light for your aquarium, you should keep in mind daylight.

If natural light is enough, then do not light up additional lights and optimize it.

Effect of Light temperature and intensity on aquarium plants

Light temperature and intensity for plants are compatible with the natural light source. The color temperature of sunlight is above the 6000-kelvin scale.

We need to determine the maximum and minimum range of it for the plants. 

For beginners aquarists, a low light plant is the best choice which is easy to grow and needs less maintenance and effort for its thriving.

You can use bright and horticulture lighting with a high spectrum for better terrestrial plant growth.

 Low, medium and high light has a different effect on them according to their kind. Some plant species like Anubias, Ferns, and Crypts can grow better at low-intensity light.

In this way, stem plants and few other species need medium-light for their best nourishment.

High-intensity light best for the plants but need CO2 for these plants’ rapid growth and control the algal bloom and activate the photosynthesis process.

Problems appear with it, so many aquarists prefer to grow the low and medium lightning aquatic plants. In all three mediums, the duration of light is meet with the standard.  

The wattage of light

It also has a significant effect on plant growth. The light wattage factor depends on the size and depth of the aquarium.

A small aquarium with a depth of less than 18 to 20 inches needs 165 to 175 watts of power. The deep tank requires a lot of light energy, about 350 to 400 watts.

For the proper maintenance of plants, the amount of 3-5 watts of lightning enough per gallon of water in a planted tank. 

Manufacturers provide you the various option of wattage for the same LED heatsink fixture. For example, 18 and 24 LEDs have 1 watt and a 25 watt for the 10-12 heatsink fixture. 

4-6 watts of fluorescent grow light are considered bright light. While 2-4 watt sufficient for the medium-light to initiate the growth of the plant.

Another is the low light which is below the 2.0 watt of grow light. It is enough for some species of aquatic plants growth like java moss, fern, water sprite.

Comparison of Different Light Sources for Aquarium Plants

The selection of lightning for your aquatic plants depends on the nature of your plants. There are different criteria for different species of it.

What are Grow Lights?

Grow light is also the best source for your aquatic plants. The light spectrum of it has a similarity with the natural source of light.

For the plant nourishment, it gives the specific color, temperature intensity, and luminous efficiency. 

Fluorescent bulb

Fluorescent tubes are available in two options T5 and T8. The most popular and ideal option for you is the T5 HO fluorescent bulb.

Its bright light has the best result on the proper aquatic plant growth. These are long-lasting, its life span is around 20,000 to 22,000 hours.

It dissipates low heat in the aquarium and cost-effective for you.

LED lights

Most of the aquarists use the LED for a planted light tank. It can consume less power and give a sufficient brightness level for your aquatic plants.

These also have the dimmer feature, which optimizes the light intensity.

Each tank has a different photosynthetically active radiation need, so it is beneficial for you. You can use some light type with standard lighting that is sufficient for them.

Halogen lights

Halogen light has enough intensity and suitable for the large-sized aquarium. It dissipates heat which sufficient for the large volume of water.

It alone cannot favorable for these plants. However, when combined with the natural source or other forms of supplemented light, it allows plants to thrive.

Blue light

There is a lot of benefit of blue light. It can lighten your aquarium and enhance the physical activity of aquatic inhabitants.

It cannot affect the fish sleeping cycle and growth of algae. It is also better for fish tank plants. Blue light is suitable for photosynthesis and has excellent penetration into the water.

Plant growth and the calming effect of the aquarium is achieved by the blue LED light. It is a combination of blue, red, and green colors and uses it according to the nature of plants. 

Aquarium Lights ON Duration According to Different Plants

The photosynthesis process releases a sufficient amount of oxygen needed for plant species, so various fish species use this oxygen in the aquarium for survival.

Plants species are different and require light according to the need, as some grow better at dim light while others at bright light. It is essential for their photosynthesis and makes food from water and CO2.

Carpeting plants also consider as a bed of grass like it cover the aquarium base. When these are under the exposure of light, their demand also varies.

Dwarf Baby Tear and Glossostigma Elatinoides are two species with different light requirements that are ideal for small aquariums but need bright light. In this way, Java Moss grows well at low light and easy to grow with less maintenance. 

Green Tiger Lotus and Echinodorus tenellus is the mid-ground aquarium plant. They need an optimum light, like not too low or high.

Another is the Anubias Nana need low light with less maintenance requirement. For its survival, you do not need too much lighting. 

Amazon sword is the background plant that acts as hidden equipment to provide the fish best hiding place.

Low to medium light is enough for their development. In this way, pondweed does not require high maintenance.

However, each plant shows a different reaction toward it, but it has no significant effect on the fish tank light.

Suitable light spectrum

Determine the best light spectrum for these plants, which has a significant impact. You can identify it by the color temperature or Kelvin rating.

The natural light source has a more than 5,000K range, so select according to this standard. You have the option of red, blue, and green light with a different spectrum. 

Plants need more red light for photosynthesis than other types of light. The best-recommended combination for you is to use 45%-50% of red and above 10% of blue and green, which lie between them.

In this way, you can provide the optimum environment for the stimulation of plant growth. You have to do some research about your aquatic plants and their proper needs.

The red spectrum is suitable for the shallow tank as compared to the other because its absorbance in water is easy. Others are suitable for the deep aquarium. 

signs of too much light on aquarium plants

Anything deficiency and excess cannot have an efficient result. If you keep the aquarium lights on 24/7, it can cause some negative impact.

The algae growth high which is harmful to fish and plants. 8-12 hours is sufficient for their survival. If it exceeds their limit, they will interfere with your fish sleeping cycle.

It also exerts a poor impact on their health, like the immune system. Some light types dissipate heat which is not suitable for a small aquarium.

It enhances its water temperature, which can fade and kill your plants. You should avoid excessive hours of lighting and monitor the water temperature regularly.

Poor effects on plants produce like fade and eventually die if you cannot provide the light source. Excessive light prevents its nourishment and facilitates algae bloom, which affects its health.

Related Articles:

How long can aquarium plants live in a bag?

How is tap water safe for aquarium plants?

How to Put Succulents in a Fish Tank?