Aquarium lighting today is at a better point that it has ever been before.
There has never been a greater range of aquarium lighting available nor has the technology been so useful.
The problem with this is that there are lighting setups available for your aquarium ranging from free (comes with your new aquarium) up to €1000+.
This leaves quite a large range of products which means more chance that you will end up making the wrong choice.
Of course nobody wants to buy the wrong thing so we have compiled a guide for you. When you have read through this article you will have a better understanding of what lighting system you need for your aquarium.
Aquarium lighting first and foremost illuminates your aquarium.
The lighting is there to allow you more easily see your fish and other contents.
The lighting also helps to boost the health of your fish, plants, live rock, etc.
When you are looking for a lighting system for your aquarium it is best to consider the light available to the fish in their natural habitat.
- If you have fish which naturally exist in shallow rivers in the amazon you will need high intensity light.
- If you have fish which naturally exist in deep ocean areas with very low light levels you could harm the fish with high intensity light.
Kelvin Rating –
Most of the time when we carry about our day we don’t consider what colour the light we see is but all light has a colour of some sort.
Without getting too much into the science of it all, light is a wave which is blue at the highest wavelength and red at the lowest wavelength. We see this in a rainbow as the light spectrum is split up in the rain.
This is relevant to keeping fish because as sunlight travels through water the lower wavelengths are removed. From 15 feet the red spectrum has been removed and by 50 feet of water only the blue remains.
If you have coral which exists usually at around 30-40 feet below the surface of the water then you will need a lighting system which can supplement blue light rather than white light which holds all the colours in the spectrum.
Watts –
The power of a bulb in measured in watts. The more powerful the watts the stronger the light.
Different tanks will require different levels of light and one of the easiest ways to get a starting idea of what light you have and what light you need is by looking at the wattage of your bulbs.
Here is a rough guide –
- Low light requirements are between 0.3 – 0.5 watts per litre of water.
- Medium light requirements are between 0.5 – 0.8 watts per litre of water
- High light requirements are upwards of 0.8 watts per litre of water.
As an example if you have a 200 litre tank with just a few tetras in it, they will not need a lot of light. If you want to have 0.4 watts per litre then you will need 80 watts.
If you have a 200 watt tank and you want to keep live rock in there along with some plants and some reef friendly fish while you’re at it. You might need 1.2 watts per litre for this intense tank. That would be 240 watts for your 200 litre tank.
This is by no means the best way to work out how much light you need but it is a good starting point.
Aquarium Lighting Type Guide
Fish only aquarium Lighting –
Most new aquariums come with two bulbs to simulate day and night. This is advertised as a requirement to make your fish healthy. Since most fish are non-photogenic organisms and no not require sunlight for their maintained health this is just some clever advertising.
If you are buying a new aquarium and you get the day and night bulbs with it then don’t worry about it, they are still good bulbs and will be useful if you graduate to aquarium plants.
If you are buying a new aquarium lighting system and you only keep fish in your aquarium you can focus more on cost and aesthetics with your aquarium lighting.
Freshwater Planted Aquarium Lighting –
Firstly whenever you are putting plants into an aquarium the light you require will depend on the plant.
A rough guide would be to have 1 watt of light energy for every litre of water.
A high level of aquarium lighting will result on additional heating on the tank. This means that you will need to have a cooler for your aquarium to regulate the heat.
You will also need to keep the aquarium a room which does not suffer from extremes of temperature.
If you are keeping aquarium plants you will want to make sure not to have the aquarium fully lit for more than 12 hours of the day. The plants will not benefit from the extra light and you will only promote algae growth.
Saltwater Reef Aquarium Lighting –
Coral and invertebrates in a saltwater aquarium rely on lighting for their survival. A common misconception is that coral and invertebrates require high intensity of light to survive.
Since many different species exist in different levels and conditions of water naturally, different intensities of light are required in your aquarium.
Generally speaking coral will require an aquarium lighting system with a blue rating of cold light. This means that the red, orange, yellow and green light spectrums will have been blocked by the water before it reaches the coral in the wild. You have to simulate this with a light system which does not project these colour spectrums.
As a guide if your tank is more than 24 inches deep then you will need to provide 1.2 watts of light per gallon of water for adequate lighting for coral or invertebrate growth.
If your tank is less than 16 inches deep (roughly the minimum your tank could be) then you will need to provide 0.4 watts of light per litre of water.
If your tank falls in the middle you can go with 0.8 watts of light per litre of water.
These are not specific numbers and will vary depending on the coral or invertebrate so research your species first.
Combing aquarium lighting types
Since coral requires blue light to survive you will need to have a blue light in your aquarium lighting. The problem with this is that an aquarium doesn’t look very nice when showered in blue light.
To make your coral grow but still have a nice looking aquarium it is often best to combine a specifically blue light like a actinic bulb with a normal fluorescent bulb. This gives the coral the required blue light while also bathing the aquarium in enough of the other colour spectrums to look good.
Whenever you are looking to update your aquarium lighting setup the most important thing is to take into account what will be in the tank and the light that these inhabitants will require.
If you do some quick research and use the information we have provided here you should be in a great position to have the perfect aquarium lighting setup.
Aquarium lighting can be tricky and to be honest this article only covers the basics. To make sure you get the right lighting to suit your needs you need a more substantial guide.
While we can’t provide as in depth a guide here we can recommend the excellent Ultimate Secrets for Saltwater Aquarium Fish and Invertebrates.
This is an excellent companion for anyone looking to setup an aquarium from the small casual hobby tank to the complex home aquaria. Their chapter on aquarium lighting is what is important in this case and it gives a breakdown of what light you need for different aquarium types and capacities.
The book is filled with other useful information and with all that you will get from this book taken into account it is great value for money.