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Home > Goldfish > Goldfish Tank Light Tips for Healthy Fish: Complete Guide 2024

Goldfish Tank Light Tips for Healthy Fish: Complete Guide 2024


Goldfish do not rely on lighting as plants do, but it is still important to give them a day and night cycle. This will help their eye development and provide them with the light requirements that they would receive in the wild. There are a lot of different types of aquarium lighting that you can choose from for your goldfish. Lighting will help to enhance the view of your goldfish and their tank design.

Lighting is not particularly important if your tank is near a bright window or inside of a brightly lit room and it does not fall into the list of important goldfish tank equipment. Yet many goldfish keepers will choose to use an aquarium light to help plants grow or encourage the growth of green algae.

This is a guide on some of the advantages of light for fish and how it will help your goldfish, while still benefiting you.


Top 5 Tips When Choosing a Light for Your Goldfish

1. Type

Aquarium light types include fluorescent, LED, or UV lighting. All of these are suitable for use with goldfish and work well as a permanent lighting system. You want a light that has more of an orange glow than one that has a bright white output, as this is gentler on their eyes.

LED: Consists of many bulbs in one light fixture and produces a bright light. The color is usually adjustable with a remote.

Fluorescent: The most popular option is a standard bulb with a light fixture and produces an orange glow throughout the aquarium.

UV: Usually used with algae or bacterial growth and can be overly bright for goldfish. It should be used for uncontrollable algae growth or to treat minor bacteria in the water column.

goldfish veiltail
Image Credit: Pixabay

2. Color

Lighting color is just as important as the brightness of the light. The color should be soft and gentle for goldfish if they accidentally stare into the light. Since goldfish are naturally curious, they will most likely do this a few times throughout the day.

White: Is generally too bright and not recommended with the use of goldfish.

Orange: The most recommended and gentlest color for fish.

Colored lights: Unnatural and may confuse the goldfish.

Dim: Best used to mimic the early mornings or evenings.

two goldfish veiltail
Image Credit: Pixabay

3. Wattage

The wattage will determine how much electricity the light uses. Most aquarium lights will have the advantage of being energy-saving. This will not cause the light to use up electricity at a rapid rate since many aquarists will leave the light on for several hours. Low wattage lights are ideal for goldfish and your electric bill.

The Truth About Goldfish New Edition

Figuring out the best lighting options for your goldfish family isn't easy, so whether you're new to goldfish keeping, or are an experienced keeper, you should check out the best-selling book, The Truth About Goldfish, on Amazon. It covers all you need to know from lighting to tank maintenance advice, routine cleaning, goldfish health, and more.

4. Settings

It is recommended to use a light that has various lighting options. This may include colors, brightness, and dimming settings. These lights will be pricier than a standard fluorescent bulb but will ultimately be worth the investment. Some lights will even come with options to switch off and on by themselves using a timer. This will help aquarists who do not always have time to manually adjust the light.

goldfish in aquarium
Image Credit: Pixabay

5. Water Resistance

Since the lights will be suspended over water, and electricity and water do not mix, every light fixture should be completely water-resistant. Lights that are only splashproof will not work well for aquarium use and can be incredibly dangerous for the whole household. Accidents can easily happen, and the light can fall into the tank, which will cause a lot of problems. The fixture should be fitted securely on the top of the aquarium and shine down. The light should enter from the top and not the sides where your goldfish can easily look at it.

Image Credit: Pixabay

divider-fishGoldfish Lighting Requirements

A goldfish’s natural environment is typically open and shallow, with minimal plants to block out the harsh rays of the sun. This means goldfish receive a decent amount of light during the daytime. They are also exposed to a variety of elements like rain and cloud cover. Goldfish lighting requirements are flexible and dependent on the type of goldfish you keep. Single-tailed goldfish have better eyesight than fancy goldfish. This makes them more sensitive to the types of lights you use over their aquarium. Fancy goldfish are generally quite inbred and have poor eyesight regardless of the light they receive.

Some lights will be too bright for a goldfish and can cause eye strain if used over a prolonged period. This makes the color of the light important and you will get to choose between an orange to brown color, red, blue, green, or a white LED light.

Goldfish require a mild to moderate amount of light between the span of a few hours.

Day and Night Cycle

All fish should have an established day and night cycle. Fish do not have eyelids and rely on total darkness to rest. Without at least 8 hours of darkness, your goldfish can become sleep-deprived. This means you should turn off all lights before you go to bed to ensure your goldfish can rest peacefully. Blue or red lights should also be turned off as goldfish do not require night lights and appreciate complete blackness to truly rest and regain their strength. Allowing your goldfish to experience more than 6 hours of darkness will have a positive effect on their health. A well-rested goldfish is healthier and more active.

Aside from a period of darkness, goldfish also need moderate lighting in the day to mimic the daylight they will receive in the wild. Some lights will come with a dimming option which is great for dawn and dusk!


Goldfish Eye Health

The light you decide to use in your goldfish tank should not burn their eyes and cause them to hide. Goldfish can be particularly skittish when it comes to switching on the light and can cause shock. This is because their tank is going from darkness to a rapid change of bright light. It will cause them to hide and be less active than usual.

There are a few ways to help you determine if your aquarium light is too bright for your goldfish:

  • Clamped fins when you turn the light on
  • Erratic swimming
  • Knocking into the walls and decorations in the aquarium
  • Hiding under the filter or objects inside of the tank
  • Struggling to find food
  • Lethargy

Luckily, most of these signs will go away once you turn the lights off or change the brightness setting.

pearlscale goldfish_Juan Carlos Palau Díaz_Pixabay
Image Credit: Juan Carlos Palau Díaz, Pixabay

Lights and Plant Growth

Leaving the lights on in your goldfish tank may cause the rapid growth of algae. This can be undesirable for many goldfish keepers and cause them to discontinue the light. The main problem is the amount of time the light is kept on. If you keep the light on for long hours, spanning between 7 to 11 hours, algae will take advantage of this and rapidly establish itself. You can get rid of algae using algae eaters, a UV light, or reduce the amount of time the light is on for.

Housing a goldfish isn't as simple as buying a bowl. If you're a new or experienced goldfish keeper who wants to get the setup right for your goldfish family, check out the best-selling book, The Truth About Goldfish, on Amazon.

The Truth About Goldfish New Edition

It covers all you need to know about the ideal tank setup, tank size, substrate, ornaments, plants, and so much more!

Enhancing Goldfish Colors

Lighting can help you to see your goldfish better and bring out the best of their colors and patterns. Most healthy goldfish will have shiny and vibrant scales that glisten underneath artificial lighting. Paired with a good quality diet, aquarium lighting can help your goldfish reach its full-color potential.



Brightening up your goldfish’s tank does not have to be overly confusing if you ensure the light meets the conditions to be safe for goldfish. Always make sure electrical outlets where the light is plugged in are out of harm’s way from spillage or leaks. Following the tips and guidance in this article can help keep your goldfish healthy and happy under a lighting system. There are so many options out there to suit your tank and needs. Artificial lighting can be a fun way to bring out the best in your aquarium.

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Featured Image Credit: dien, Shutterstock

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