Choosing Aquarium Lighting: Everything You Need To Know

An often overlooked aspect of the aquarium hobby is lighting. Not only does a proper lighting system add to the aesthetic appeal of your aquarium, but it’s also crucial for the well-being of your fish and for the growth of your aquarium plants.

Always consider the fact that your new fish has evolved to live in certain conditions in the wild. To care for them correctly, the natural living conditions need to be replicated as closely as possible. Since most tropical fish and freshwater plants are found in streams and other small bodies of water, they are accustomed to the bright, warm rays of the sun.

Choosing a bright lighting system with a color temperature between 6700k and 10,000k would be ideal for most home aquariums. The color temperature of the sun is 6700k, so anything between these two figures will work well.

For heavily planted aquariums, a light bulb with a color temperature closer to 10,000k would be better suited. Different plants have different light requirements to properly photosynthesize, so knowing your plants’ requirements can help you make the right decision.

The Benefits of Proper Aquarium Lighting

There are three main reasons why effective lighting is necessary for the health of your aquarium. The first, and probably the most important is for the health of your plants. I don’t remember much from my biology class at school, but thankfully the memory of photosynthesis stuck around. Who would have thought it would come in handy?

Plants typically have a phyto cycle of around 8 hours. Give them 8 hours of bright light per day and they will comfortably thrive. Give them too much or too little and you run the risk of upsetting the balance of the ecosystem. It’s a simple game, but it’s super important for the health of your aquarium, so keep this knowledge in mind.

It’s not only plants that require sunlight either. Your fish also need plenty of light in order to reach peak health and to be in unison with a natural cycle. The bright light will also help the darken the pigment of your fish, allowing them to reach their full colour potential. This brings us on to the next point, which is the aesthetics of your tank.

A well-lit aquarium is a good looking aquarium. Lights can help you see what’s going on in this underwater world that you have in your home. It allows you to see the full colors of your fish, their behavior and how they interact with each other, the color of the plants and the cleanliness of your aquarium. Simply put, good lighting brings your aquarium to life!

LED vs Metal Halides vs T5 Fluorescent

The three main types of lighting that dominate the market are LED (the most common), metal halides and T5 fluorescent. Of the three, LED is king. LED lights are cheaper to run, relative to the amount of light that they produce. They also produce no heat, which is often a huge problem with incandescent light bulbs. Too much heat from lighting systems can fluctuate the temperature of the water which is potentially dangerous for your fish.

Metal halides are easy to setup and can offer a shimmering effect to the water, but they are more expensive to run and can  produce a lot of heat. If you have a deep tank and like the natural, shimmering effect that halides can provide then they are still a sufficient choice, but in all other circumstances, I would recommend LED.

T5 Fluorescent bulbs are newer to the market and have considerably better technology than the metal halides. They are brighter, require less energy and can provide consistent light to every inch of your aquarium. You won’t get a shimmering effect with these, rather a consistent, even glow. The problem with T5’s is that they need replacing more often and the specialized globes can be difficult to find and are usually quite expensive.

The lighting system that I recommend in most cases is an LED lighting fixture. LED bulbs use the latest in technology, meaning the performance is amazing, but with better cost-effectiveness.

A single LED bulb can last up to 50,000 hours before needing to be replaced and the bright, crisp light can cover the entire length and breadth of your home aquarium. LED’s are also lightweight, easy to install and produce little to no heat.

With that being said, LED light setups can sometimes cost more than the alternatives, upfront. Believe me, though, it’s always better to fork out a few extra dollars upfront to install LED lighting than to constantly stress and worry about inferior lighting systems.

However, that’s not to say that LED lighting is expensive. The hood that I use for my aquariums is the Koval 12, which is inexpensive and has never given me any issues to date.

It’s extendable to fit all tank sizes, the full-spectrum bulbs last forever and can produce different colors depending on how I want the tank to look. It’s an ideal hood for any freshwater aquarium and I highly recommend it.

How Long Should Aquarium Lights Be On?

A common misconception and error that new aquarists will make is to keep the aquarium lights on constantly. Not only is this a waste of electricity, but it’s also inefficient for growing plants and can drastically damage the health of your fish.

Both fish and plants need both light and darkness during a 24 hour period. They are living organisms that operate on a cycle, just as we do. Plants and fish can only absorb so much of the light rays before it turns detrimental. That length of time is debatable and can vary from species to species.

As a general rule of thumb, it’s recommended to provide 12 hours of light and 12 hours of darkness. Keep your aquarium out of direct sunlight if you want to have tighter control over the timings. After around 8 hours, plants and fish have received enough benefit from the light to satisfy them for the night, so it’s a waste of energy to keep the lights on any longer.

Managing Lights When You’re Not Home

If you’re away on vacation, or staying somewhere away from your aquarium for a long period of time, it’s a good idea to invest in an inexpensive mechanical plug-in timer. Simply set the time that you want the plugged in appliance to turn off and on, switch it on and you are good to go.

Leaving the lights on constantly while you are away is a recipe for disaster. Too much light can quickly encourage algae to takeover your tank and the overall equilibrium and balance of your underwater world will be thrown off.

So, Aquarium Lights Cause Algae?

Not if you do things properly!

I know, that’s a bit of a cop out answer, but hear me out. Algae is typically caused by a high nutrient value in the water. It’s typically the worst at the start of a new tank, before everything has had a chance to effectively finish it’s cycle to create balance and equilibrium.

Bright lights can encourage algae to grow, but after a while things will balance themselves out and the lighting will have little to no effect on algae. If you are still suffering with algae problems after a few weeks of setting up a new tank, or installing a new lighting system, the problems could be caused by other things.

We have an in-depth guide to teach you all about algae and how to control it. Check it out, it’s incredibly useful information that all fishkeepers should know.

What Kind of Tank Are You Creating?

All of this is not to say that every tank should have the same lighting parameters as each other. It all depends on the type of aquarium you are creating and the life that will be living inside it. Some aquarists prefer a darker, heavily planted aquarium with bottom feeding fish who thrive in a darker, murkier environment. Some prefer a spacious, brightly lit community tank with lots of action. It all comes down to personal preference.

Understand what type of tank you are creating, then plan your lighting system accordingly. A good LED hood will cover all of the bases and will allow you to customise your aquarium according to your requirements.

We love to hear back from our readers, so if you already have an aquarium set up, we would love if you could share some insight into what lighting you are currently using and whether or not you would recommend it to a friend.

I can also personally reply to any questions that you may have about aquarium lighting, so don’t be afraid to comment below or reach out to us on Facebook.