How to Balance Aquarium Lighting to Grow Healthy Plants (And Avoid Algae)

How to Balance Aquarium Lighting to Grow Healthy Plants (and Avoid Algae)

A brand-new planted tank always looks so beautiful and pristine, but if the tank is unbalanced, those same plants may become sickly-looking and overrun with algae within a couple of months. Plants and algae both use the same resources- such as light, nutrients, and carbon dioxide – so the goal is to balance these resources so that the plants grow stronger and outcompete the algae. Too much of a good thing can lead to too little.


Too much light can lead to algae growth so it is important that we fine-tune the lighting for optimal plant growth. Let’s now discuss how to adjust the lighting for the tank and plants you choose.

Remember that plants are living organisms and will take time to adjust to changes in lighting. We recommend that you make one adjustment per aquarium, and wait two weeks before making another. You will not know the results of multiple changes if they are made at once.

1. Location

For optimal control of the lighting, avoid placing your aquarium in direct sunlight. You may need more sunlight than you think, especially if your plants are low-light. You also have to consider the unpredictable weather. It may be sunny one morning and cloudy another. Each season is different. Yes, some experienced hobbyists can manage planted tanks that get sunlight, but for most of us, the fluctuating changes make it difficult to balance the aquarium because the plants are getting widely varying amounts of light every day.

2. Equipment

A light specially designed for aquarium plants will create the perfect environment for your underwater garden. Aquarium kits come with default lights that are too dim. Shop lights and other DIY lighting options may not be as effective or spread the light well enough to produce a pleasing color temperature. The best tank lights are optimized for aquarium plants. The best lights have the right brightness, good spread that won’t shine into your eyes, and a natural color spectrum that makes fish and plants look their finest.

Use a timer to create a regular schedule for the light to turn on and off each day.

3. Light Duration

Put your light on an electrical outlet timer so it turns on and turns off at the same time every day. Timers are much more reliable than people, so even if you get sick, go on vacation, or just plain forget, your plants will get the light they need. We recommend that you only light your aquarium for 6-8 hours per day when it is first planted. This will allow the plants to adjust to their surroundings. When the plants become larger and need more light to grow properly, you can gradually increase the lighting time to 8-12 hours per night. If algae starts getting out of control, then decrease the duration again. Some hobbyists like to split up the timing of the photo period with an “afternoon siesta” so it turns on in the morning while you’re eating breakfast, turns off while you’re at work or school, and turns on again at night when you’re back.

As a reminder, do not leave the light on all night, not even in blue moonlight mode. Every night, the plants must rest by entering the respiration cycle to consume oxygen and sugars. Even if the light is on constantly, they won’t photosynthesise. This means that algae can take advantage the extra photons and overtake your aquarium.

4. Light Intensity

Most planted tank lights nowadays are made with LED technology and are powerful enough to grow both low and high light plants. A light intensity of 100% may cause algae growth depending on the plant you choose and the tank height. Begin with a low light intensity, around 20-40% brightness. If no algae growth occurs, increase the intensity gradually. If a significant algae bloom occurs, then lower the brightness again. If the dimming setting is not programmable, you can raise the light or use black electrical tape to block out the LEDs.

Aquarium lighting available in various brightness levels and colors

5. Fine-Tuning

Even after you balance the light duration and intensity, remember that aquariums are ever-changing ecosystems and therefore may need further adjustments in the future. Because the plants are still growing and small, a newly planted tank requires less light. However, mature tanks might have large plants that shade everything. In these cases, you may need to reduce the light or increase it. To balance planted tanks, it is helpful to keep track of your lighting settings over time in an aquarium journal or spreadsheet so that you can identify the most effective values.

What is the Best Lighting for Plantted Aquariums?

When picking an aquarium light, there are many options on the market that range from relatively inexpensive to extremely steep. The key is to determine which features are most important to you and the type of planted tank you want to set up. Also, you want to pick a good quality brand that will last, rather than buying the cheapest option that has a very short warranty and LEDs that go bad after a few months.

Easy LED Plant

Our search for a light source that is both affordable and long-lasting to make plants look stunning led us to create our Easy Plant LED. It features all of our favourite features like:

– The 3-year warranty and lights rated for 50,000 hours of operation – The high-quality, energy-efficient LEDs that bring out the stunning colors of fish and plants while reducing power usage by 10-50% – The highly water-resistant IP67 rating so it won’t fail from accidentally dropping in water or getting splashed by an air stone – The easy-to-use controller for changing between white Daylight and blue Moonlight modes – The dimmable light settings that allow you to adjust the brightness from 10-100% to grow both high and low light plants – The extra-long, 12-foot power cord so you reach even the furthest outlet in the room – The extendable sliding brackets to make sure you get a snug fit and prevent light from bleeding out – The thick aluminum frame to dissipate heat from the LEDs and prevent bowing in longer models

Our goal is to make the fishkeeping and planted tank hobby as easy as possible, which is why we created the Easy Plant LED as a dependable, all-purpose solution that produces excellent plant growth. Our Easy Green and Easy Root Tab fertilizers are the perfect combination to create an Easy Planted Aquarium.