So, you’ve bought your fish and they’ve made themselves at home in your fish tank. But should you leave fish tank lights on all the time?
Most fish need around 12 hours of daylight and 12 hours of darkness each day. However, you don’t need to turn your fish tank light on for a full 12 hours every day, as natural light should be bright enough to fill a few of these hours.
Don't keep fish in the dark
Fish that live in the dark all the time tend to have weak immune systems. This makes them more likely to fall ill. A lack of light can also cause some fish to lose their colour.
Instead, fishkeepers should create cycles of light so their fish can distinguish between day and night. The natural light in a room will help fish to follow a cycle of light. But you can make this easier for your fish by turning on the light unit in your aquarium during the day.
Bonus Tip
Different rooms have different levels of natural light, so your room might be lighter or darker than average. You should keep this in mind when deciding where to put your fish tank.
Consistency is key when creating a light cycle for your fish. If you won’t be around to maintain a consistent light pattern, it’s a good idea to buy a timer socket for your fish tank. You can get budget timer sockets, smart plugs, or advanced fish tank LEDs with advanced timer functions. More on that in our previous blog post: Do fish need light in aquariums?
Avoid algae growth
If you leave your aquarium light on for too long, you’ll promote algae growth. Therefore, we recommend leaving your fish tank light on for 8–10 hours a day. It’s fine to experiment with these hours to monitor how much algae growth you get in your fish tank and adjust accordingly.
Don’t leave your fish tank light on for longer than this or your fish will struggle to find their rest period. Fish don’t sleep in the same way humans and other mammals do. But they do rest, often at the bottom of the tank.
Bonus Tip
Different fish species need different exposure to light. While their needs shouldn’t differ too much, it’s a good idea to ask the pet shop how much light your particular fish species needs.
Turn your fish tank light on for your plants, too
If you’ve got live plants in your fish tank, remember that lighting is important for these as well. Plants need light for photosynthesis, which is key to maintaining a healthy aquarium.
Know which fish tank lights you need
The type of fish tank light you need depends on your aquarium. We’ve already written a blog post to help you work out whether your fish tank needs a T5 fluorescent tube, T8 fluorescent tube, or an LED light. We sell individual light tubes and complete light units to replace all three.
If your tank uses T5 or T8 fluorescent tubes, you might like to upgrade to an LED aquarium light (which is far more energy efficient). And, if you’re a Juwel fish tank owner, we’ve written a blog post specifically for your LED upgrade.
About Warehouse Aquatics
The Warehouse Aquatics mission is to offer the most choice at the best prices when it comes to your fishes’ wellbeing. We use the products on our website ourselves and are well-versed in all things fish, so we can give you all the advice you need. We’re not just here to sell aquatic supplies. We’re also here to guide you through your journey as a fish owner and enthusiast.
As a small team, we love to hear from our customers, so please do join the Warehouse Aquatics social media community. We’re always up for a chat, and we’d love to share your aquarium photos with our followers.