This is the Best Turtle Basking Light Wattage main picture
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UV lights come in different watts, such as 50 and 100-watt bulbs. In this instructive article, I’ll teach you what is the best turtle basking light wattage.

Pet turtles need a lot of things to stay healthy. They need an adequately sized tank, a basking spot, good food, clean filtered water, and UV lighting.

With UV lighting, you really only need to check 2 things:

  • That it has UV-A and UV-B light.
  • That the basking spot the light is pointed at is at the correct temperature.

How many watts the light-bulb is, doesn’t matter. Here’s why.

What’s the Best Turtle Basking Light Wattage?

Let’s get straight to the point.

Watts or wattage is a measure of electrical power. It’s easy to visualize. The more watts = the more power. Or, the higher the wattage = the more electricity is being used.

Simply put, a 100-watt turtle light bulb is going to be much more powerful (and use a lot more electricity) than a 50-watt bulb.

Which begs the question, then what’s best for my turtle? The truth is this.

The Number Of UV-Light Watts Is Not Important

Wait, how is this not important?

Here’s why:

A 50, 75 or 100-watt bulb will be fine. What’s really important is that the turtle’s basking area (for most common species) is between 85 to 90 degrees (29 to 32 degrees Celsius).

Why?

Because one of your most immediate, pressing goals when setting up a proper habitat for your pet turtle is to get the temperature inside the tank or tub right.

And you do this through your UV lighting.

Here’s a closer look.

The difference is in the details. Depending on your circumstances, you may opt for a 100-watt instead of a 50.

How Many Watts Do I Need For My UV Turtle Light?

  • Do you have a smaller aquarium (around 55 gallons?)
  • Do you have 1 or 2 turtles?
  • Is your basking area relatively small?

If you said yes to any of the above questions, a 50 to 75-watt will be perfect.

  • Is your aquarium bigger, say over 90 gallons?
  • Do you have more than 2 turtles?
  • Do you need or want a larger basking area?

If you said yes to any of the above questions, you should opt for a 100-watt bulb.

Since a 100-watt turtle basking light would produce a bit more energy, it would also be able to produce more heat, as well as have a larger basking diameter. Thus, you would be able to get a large basking area to 90 degrees a lot easier using a 100-watt basking light than a 50-watt basking light.

If you’ve got a larger tank, say from 75 to 100 gallons, it’s going to be much more difficult to get to the correct temperature with a 50-watt bulb.

With 1 or even 2 turtles, this is normally not much of a problem with a 50-watt, especially if you have a smaller aquarium, or if you’ve got a smaller basking area (that is perhaps, 2-3 lengths of your turtle).

How Far Away Should The UV-B Light Be From A Turtle?

Another practical difference is how close you will need to place your basking light to your turtle.

Because your goal should be to maintain a basking area with a temperature of 85-90 degrees, you will certainly need to place a 50-watt light closer than a 100 watt light.

Usually this distance is between 8-15 inches, however, you will need to both check the instruction manual on any light you purchase as well as manually take the temperature of your basking area once it’s all set-up.

  • A 50-watt light will need to be placed around 5-7 inches away from the basking area.
  • A 75 watt light will need to be placed around 7-9 inches away. 
  • A 100 watt light will need to be placed 10 to 12 inches away. 
  • A 150 watt light will need to be placed over 12 inches away.

Again, these are general rules of thumb, as things such as the surface of the basking area and material will all play a role in how close or far you need to position your light.

UV Basking Light Safety Precautions 

One thing that absolutely, positively, needs to be mentioned here, purely for safety concerns, is that although your light wattage doesn’t really matter, you must make sure that your light fixture can handle whatever light wattage bulb you have.

You don’t want to screw in a 150 watt light bulb into a fixture that is only rated for up to 50 watts. It will likely burn the fixture, and worse, can potentially start a fire.

Check your light fixture’s wattage rating before screwing or purchasing any reptile light.

So, the main point here is to get the temperature of the basking area right. That’s the sole focus here.

This is extremely important, as:

  • Turtles will avoid a basking area that is too hot and not get UVA and UVB light.
  • Your turtles will not get enough UVA and UVB light under a basking lamp that is too cold. This can lead to very deadly respiratory infections.

Can A Turtle Get Too Hot Or Cold?

The simple answer is that yes, a turtle can get too hot or too cold.

If your turtle gets too hot, it will probably start avoiding your basking area and stick to the water. Over time this will lead to a lack of UV-B light.

If your turtle gets too cold, it will probably bask constantly and may be at risk of contracting a respiratory infection.

I know a lot of people put this off, but you really need a thermometer.

You need a thermometer because, without one, you are just guessing.

Nothing fancy, just something that is cheap and works.

Here is what you will need to do:

  • Check how many watts your UV-light is.
  • Measure the distance between the end of your UV-light and the middle of your turtle’s basking spot.
  • Use your thermometer and take the temperature in the middle of the basking area.

For most turtle species, the basking temperature should be in the high-80s to anywhere in the 90s.

Based on your temperature reading, you might need to do some adjusting:

  1. If it’s too cold, you need to either buy a light bulb with more watts or move the light closer to the basking area.
  2. If it’s too hot, you need to either downsize your bulb by decreasing the watts or simply move the light further away from the basking area.

Can I Use A Regular Light Bulb For My Turtle?

No, you can’t, unfortunately.

At least not for a long period of time.

The reason I say this is because the only 2 reasons your turtle needs a light in the first place, is for heat and for UV-A and UV-B light.

Regular, incandescent light-bulbs from your desk stand lamp can work just fine as a source for heat. In fact, many pet turtle owners use them just for that purpose. However, they don’t produce the UV-B your turtle needs to stay healthy.

The truth is that your turtle NEEDS to receive UV-A and UV-B light from SOMEWHERE. It doesn’t necessarily have to be from a light-bulb. It can come from the sun.

The reason why UV-B producing light-bulbs are so convenient, however, is that they produce heat and UV-B light, so you won’t need to take your turtle outside for hours upon hours every single day.

Summary

Whatever turtle light bulb you choose, please make sure that it also emits UVB light. This is crucial. You don’t need 1 light bulb to have everything, you can use 2, 1 for warmth and 1 for UVB (and UVA light), but you do need to ensure that UVB light is at least hitting your turtles, daily.

This is why:

  • Turtles need UV-A light, which is emitted naturally from most light bulbs, for healthy moods, feeding, and breeding, as well as general light that mimics the sun for most of the day.
  • Your turtles need UV-B light for the healthy production of vitamin D3, which helps with their bone and shell growth. Turtles that do not have access to UV-B light often develop chronic bone diseases, which are painful and slowly kill them.
  • Your turtle is relying on you to provide a safe, warm, healthy, secure living environment. Everything, from the temperature of the basking area, to being able to access UV-A and UV-B light, is up to you.

So, as long as whatever light bulb you opt for can achieve these 3 things, you are well on your way to ensuring that your turtles live a long, healthy and prosperous life.

If you’d like to check out a good light for your turtle, check out this article on the Best Turtle Light Bulb.

About the Author

Hi, I'm J and I'm the chelonian-obsessed creator of this website. Feel free to leave a comment below, as unlike a snapping turtle, I promise I won't bite!

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