How to Choose Aquarium Lighting for a Planted Tank
Lighting is one of the most important, and most misunderstood, parts of a planted aquarium. Too little light and your plants stall or melt; too much and you invite an algae outbreak. The good news is that choosing the right light is simpler than it looks once you match the fixture to the plants you want to grow. This guide breaks down how much light plants actually need, how to pick a fixture, and how to run it without feeding algae.
How Much Light Do Aquarium Plants Need?
Plants are usually grouped into three broad lighting categories: low, medium, and high. Low-light plants like anubias, java fern, and many cryptocorynes thrive under modest lighting and are the easiest to keep. Medium-light plants, including most stem plants, want a bit more intensity. High-light plants and carpeting species demand strong, focused light and usually pressurized CO2 to keep up.
If you are just getting started, aim for a low-to-medium light setup. It grows a huge range of attractive plants, is far more forgiving, and dramatically lowers your risk of algae. You can always add more light later as your skills grow.
What to Look For in an Aquarium Light
A few features matter most when picking a fixture. Full-spectrum output gives plants the wavelengths they use and makes fish colors pop. Adjustable brightness lets you dial intensity up or down to match your plants and fight algae. Coverage matters too, so choose a light sized to span the length of your tank. Finally, an adjustable or extendable mount makes it easy to fit different rimless or rimmed tanks.
We carry a range of dependable full-spectrum LEDs in our Hygger LED lighting collection, with fixtures from roughly 14W up to 32W to suit nano tanks through larger aquariums. If you are unsure which wattage fits your tank, stop by the store in Cheyenne and we will help you match one.
Photoperiod: How Long to Run Your Light
Longer is not better. Most planted tanks do well with a photoperiod of about 6 to 8 hours per day. Plants only use so much light before the excess simply fuels algae. A simple outlet timer that turns the light on and off at the same times each day keeps things consistent and takes the guesswork out of it.
If you notice algae creeping in, the first two levers to pull are usually shortening the photoperiod and lowering intensity, before you change anything else.
Matching Light to Your Plants and Tank
Think of light, nutrients, and CO2 as a three-legged stool. If you increase light, your plants will want more nutrients and carbon to match, or algae will take the surplus. That is why a balanced low-tech tank, with modest light and easy plants, is so stable and beginner-friendly.
Pairing your light with the right plants is half the battle. Browse our low-light aquarium plants for forgiving species, or the full live plant collection for more options. For more on building a stable, low-maintenance setup, read our guide on how to set up a low-tech planted tank.
Common Lighting Mistakes
The most frequent mistakes we see are running the light too long, running it too bright for the plants on hand, and placing the tank where it also catches direct sunlight. Each of these tips the balance toward algae. If plants are melting or refusing to grow despite plenty of light, the issue is often nutrients or CO2 rather than the fixture itself. Our article on why aquarium plants melt covers those causes in detail.
Final Thoughts
Choosing aquarium lighting comes down to matching the fixture to your plants, running a sensible 6 to 8 hour photoperiod, and keeping light, nutrients, and CO2 in balance. Start modest, watch how your plants respond, and adjust from there. If you would like help picking a light for your specific tank, our team at Tropical Treasures Wyo in Cheyenne is always happy to point you to the right fixture.