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Aquarium lighting is not just for aesthetics or convenience. It is a life-sustaining function for the living organisms in the tank. Soft aquarium lighting can easily add to the atmosphere of a room, but it is crucial for the fish and plants in the tank to benefit.

Great Lights To Get Your Levels Right

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Amount of Light Required

Generally speaking, your aquarium needs eight to twelve hours of lighting every day using lights specially designed for fish tanks. How much light your tank needs depends on four crucial details: your fish species, your plants, available ambient lighting, and algae level.

Fish Species

The good news is fish aren’t that sensitive to light, which means they are often unaffected by whether you increase or decrease your lighting. Some species, though, like tetras and cichlids, are more comfortable in less light.

Tropical fish often need a mix of ambient and tank lighting for about 12 hours, while cold-water species like goldfish and minnows may appreciate varying amounts of light throughout the year. The key is to research your species and find out how much light is provided by their natural environment. You will be able to make a better-informed overall decision going into the aquarium, knowing your fish.

Aquatic Plants

Planted aquariums need dedicated lighting because the plants use it for photosynthesis. Photosynthesis is the process by which they make their food. While the general rule for planted tanks is 12 hrs/day, it all depends on the aquarium’s setup and the types of plants you have.

The amount of light provided should also blend well with the plants’ natural environment (tropical, cold-water, etc.). Every time you add new plants to your tank, let the light stay on for longer than usual, so the roots have time to establish themselves.

When choosing aquatic plants, you should also consider the fish species in the tank (for example, tropical plants for tropical fish, cold water-plants for cold-water species, etc.). If there is a discrepancy between plant-life and fish, your lighting needs could get complicated.

Ambient Lighting

Ambient light, or the natural light of the room, is another crucial factor when deciding how much extra light you need to add. You may not even have to supplement with lighting fixtures, although chances are you should. If you already have good ambient lighting in the room, you won’t need to add 12 hours-worth of extra brightness.

Light and Algae Levels

If you’re having algae issues in your fish tank, too much light is likely the reason. Since excess light promotes algae growth, reduce your aquarium lighting to 8 hours a day. If anything, reducing light hours in your tank will help you get a sense of whether you’re using too much light or not. Also, keep in mind that natural light creates more algae.

If your tank is by a sunny window, you do not need as much added light.

Auto Lighting Control

One thing that keeps aquariums from receiving the appropriate amount of light is owner negligence. This could either be from general laziness or being too busy to turn the lights on or off as needed. Luckily, you can buy a timer that can be set to adjust the lighting automatically as required.

Avoiding the Heat Trap

Aquarium lights don’t only produce light, but heat as well — and lots of it. Lighting known for its heat include incandescents, VHO-fluorescents, and lights with metal halide.

Such lights can increase the water temperature so much that your fish and plants could end up dying. Not that you shouldn’t use any of these lights, but if you do, check the water temperature frequently and always turn the lights out before you go to bed.

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Here are other options for aquarium lighting:

  • Standard fluorescent lights: To stay on the safe side, you might want to use standard fluorescent lights instead, which run a lot cooler. If left on accidentally, even overnight, the danger of overheating will remain at bay. Plus, a lot of tropical fish and plants like fluorescent lighting.
  • LED: Another great choice is LED or light-emitting diodes, which are run cool. They are also cost-effective and available in plenty of attractive colors. LED lights can be customized, too, so you can enjoy your aquarium in the exact hues and style you want.

Aquarium Type

The truth is, there is no single correct type of lighting for your fish tank because it all depends on the organisms that live there and the aquarium’s size and, of course, your budget.

For fish-only tanks, all you’ll need is a simple light system that lets you see your pet(s) and tank setup. Make sure to add enough lighting for the tank’s depth and width. There’s no need to look into plant photosynthesis.

If you have both fish and plants, know that your tank will not survive with incorrect lighting. You will have to dedicate a bit more time and care in meeting the tank’s lighting needs. Light intensity is essential for these tanks. For bigger or deeper tanks, you should look into getting HO (high-output) or VHO (very high-output) lights.

Finally, if you have reefs in addition to fish and plants, you will need not only enough lighting for everyone, but also the right mix, wavelength, and light intensity.

Daytime lights combined with a single actinic lamp is a perfect choice. As light designs, intensities, and numbers can vary widely; it is essential to do your homework and possibly some trial-and-error to know which type of lighting will give your tank the best coverage.

Adjusting Light Levels For Live Aquarium Plants