Top 9 – Best UVB Light For Turtles Guide

Not to be confused with a turtle heat lamp, choosing the best UVB light for turtles isn’t simple when you look at all the different options you have available and it can be a little overwhelming knowing what is the best option to choose.

I’ve shortlisted what I think are the best turtle UVB bulbs for your turtle tank setup.

Best UVB Bulbs For Turtles

If you’re short on time and want to know the best UVA UVB light for turtles without reading the whole article, here are my top picks.👇

• Zoo Med Reptisun 10.0 UVB Mini Compact Fluorescent (Best Compact Bulb)
• Zoo Med Reptisun 22″ 10.0 T5-HO UVB Fluorescent Bulb (Best Tube Bulb)
• Mega-Ray Mercury Vapor Bulb – 100 Watts (Best Mercury Vapor Bulb)
• Zoo Med Aquatic Turtle UVB Heat Lighting Kit (Best Starter Kit)
• Fischuel Reptile Adjustable Heat Lamp with Clamp (Best Light For Smaller Tanks)

Why Do Turtles Need UVB Light?

Turtles need UVB light to help their body produce vitamin D3 which metabolizes the calcium in their diet. This is essential for keeping their bones and shell healthy.

In the wild, a turtle will absorb UVB light naturally as they bask in sunlight during the day. An indoor pet turtle needs to have a UVB light provided or they risk developing metabolic bone disease (the reptile equivalent of osteoporosis) which is extremely painful and often proves to be fatal.

Sadly, a lot of owners don’t realize just how vital a UVB light is for their turtle’s health.

But, the good news is, you can easily avoid your turtle getting metabolic bone disease by providing them with a UVB lamp that I’ve suggested in this post.

UVA vs UVB Differences

When it comes to UV light bulbs for turtles, don’t confuse UVA with UVB. They’re 2 different parts of the light spectrum and you need to provide your turtle with both if they are to live a long and happy life.

UVA light is needed to help your turtle’s immune system, mood, metabolism, breeding health, and general activity levels throughout the day.

UVB light helps them produce vitamin D3 which metabolizes the calcium in their diet to keep their bones and shells healthy.

UVC light is harmful to all living cells and should not be used at all. The earth’s ozone layer blocks out UVC which is why everything is moving towards being environmentally friendly and protecting the ozone layer nowadays.

Types Of UVB Bulbs

There are 3 types of UVB bulbs available and each has its own pros and cons.

Compact Fluorescent

A compact fluorescent bulb, as the name suggests, is a smaller bulb than a fluorescent tube and generally has a lower price point.

They focus their energy on a smaller spot in your turtle’s tank so are a good option if you only want a small area where your turtle can bask to absorb their UVB light.

There are reports of these types of bulbs causing damage to a turtle’s eyesight.

However, this can be avoided by making sure your lights are not at an angle. They need to be pointing directly down at the basking platform.

Compact fluorescent bulbs have a shorter lifespan than tube-style bulbs.

Tube Fluorescent

A fluorescent tube spreads its UVB light across a wider area within your turtle’s tank and has a longer lifespan than a compact bulb.

Because their light is spread over a wider area the light is much less intense than that from a compact bulb so you have almost no risk of damaging your turtles’ eyesight.

They are more expensive than a compact bulb and are a more complicated setup, but they have a longer life span.

Mercury Vapor Bulbs

These bulbs are an “all in one” type of bulb, providing UVA, UVB, and heat. They are convenient if you’re short on space or electrical outlets.

However, they focus their UVB light on a very small area directly below the bulb, so if your turtle doesn’t naturally bask a lot during the day, it may miss out on a lot of its UVB light.

Where the mercury vapor bulb really excels is the much wider spread of UVA light which means your turtle will get the right amount of UVA light wherever they are in their tank.

Mercury vapor bulbs are not suitable for a smaller turtle tank as they give out a lot of heat and you risk overheating your turtle.

Best UVB Light For Turtles Reviewed

I’ve picked out the best UVB bulbs based on my experience and research, so you can be sure you are choosing the best UVB lamp for your turtle.

1. Zoo Med ReptiSun 5.0 UVB Mini Compact Fluorescent (13 watts)

• Brand: Zoo Med
• Type: Compact
• Dimensions: Height 5.91″ x Diameter 1.57″
• Watts: 13
• UVB Output: 5%
• UVA Output: 30%

✅ Pros:

• Good for small turtle tanks
• Good brightness level
• Durable
• Energy efficient
• Quartz glass
• Easy to install
• Full-spectrum including UVA and UVB light

❌ Cons:

• Not good for large turtle tanks
• Doesn’t provide heat

The Zoo Med ReptiSun 5.0 is a great UVA UVB light for turtles that live in smaller tanks.

Although it provides UVA light, it doesn’t provide heat so you’d have to buy a separate bulb for that.

It screws into standard threaded sockets without needing an extra ballast so is super easy to install.

The quartz glass has great brightness and gives maximum UVB penetration depth.

Can be bought in a pack of 4 to save you money.

Not recommended for tanks larger than 20 gallons unless you team the bulb up with the Zoo Med Deep Dome or Zoo Med Combo Deep Dome to extend the UVB penetration depth by up to 30% extra!

2. Zoo Med ReptiSun 10.0 UVB Mini Compact Fluorescent (13 watts)

• Brand: Zoo Med
• Type: Compact
• Dimensions: Height 6″ x Diameter 2″
• Watts: 13
• UVB Output: 10%
• UVA Output: 30%

✅ Pros:

• Durable
• Good brightness level
• Energy efficient
• Quartz glass
• Easy to install
• Full-spectrum including UVA and UVB light

❌ Cons:

• Doesn’t provide heat

The big brother of the 5.0 above, the Zoo Med ReptiSun 10.0 bulb is great for turtle tanks over 20 gallons.

It screws into standard threaded sockets without needing an extra ballast so is super easy to install.

The quartz glass has great brightness and gives maximum UVB penetration.

Although it provides UVA light, it doesn’t provide heat so you’d have to buy a separate bulb for that.

Can be bought in a pack of 4 to save you money.

Team the bulb up with the Zoo Med Deep Dome or Zoo Med Combo Deep Dome to extend the UVB penetration depth by up to 30% extra!

3. Exo Terra Repti-Glo 10.0 Compact Desert UVB Light Bulb for Reptiles (13 & 26 Watts)

• Brand: Exo Terra
• Type: Compact
• Dimensions: 13 Watts Height 6″ x Diameter 2.1″
•                        26 Watts Height 9″ x Diameter 3.5″
• Watts: 13 or 26
• UVB Output: 10%
• UVA Output: 30%

✅ Pros:

• Available in 2 wattages
• Durable
• Good brightness level
• Easy to install
• Full-spectrum including UVA and UVB light

❌ Cons:

• Doesn’t provide heat

Next up we have the Exo Terra ReptiGlo 10.0.

Exo Terra has a solid reputation in this hobby for making quality products, and their ReptiGlo light bulbs are no exception.

Durable, with high UVB output and giving off a lot of light, they’re a great choice for your turtle tank.

Screws into standard threaded sockets without needing an extra ballast so is super easy to install.

Team the 13-watt bulb up with the 6″ Exo Terra Reptile Dome or the 26-watt bulb with the 8″ Exo Terra Reptile Dome to increase UVB light penetration depth.

4. Zoo Med Aquatic Turtle UVB Heat Lighting Kit

• Brand: Zoo Med
• Type: Compact Light Kit
• Dimensions: 9.45 x 12.45 x 3.05 inches
• Watts: 13 watts and 50 watts
• UVB Output: 5%
• UVA Output: 30%

✅ Pros:

• All in one UVA / UVB / heat kit
• Separate plugs for each lamp
• Looks nicer than 2 separate lamps
• Great for beginners

❌ Cons:

• Included UVB bulb is only suitable for smaller turtle tanks

This Zoo Med Lighting Kit has everything you need in a single package:

• 1 x Mini Combo Deep Dome lamp fixture
• 1 x ReptiSun 5.0 Mini Compact Fluorescent (13 watts)
• 1 x Repti Tuff Splashproof Halogen Bulb (50 watts)

The polished interior of the dome increases the UVA & UVB depth penetration up to a further 30% into your turtle’s tank. If the depth of UVB penetration isn’t enough, you may be better off upgrading the UVB bulb to a Zoo Med ReptiSun 10.0 UVB Mini Compact Fluorescent bulb.

The dome has separate plug sockets for each of the bulbs, so you can control both bulbs independently. The only drawback to this is you need 2 power outlets available.

The heavy-duty Repti Tuff halogen bulb acts as a heat source as well as emitting UVA light. It has a splashproof coating that prevents it from bursting if it gets hit by water keeping your turtle safe from shards of broken glass or other injuries.

There is also the option of purchasing a lamp stand for this kit, so you can safely hang the lights above your aquarium. The Zoo Med Reptile Lamp Stand comes in small and large sizes.

If you’re turtle lives in a stock tank, this light kit is a great option as it has a built-in metal hook, so that you can easily hang it above your stock tank.

5. Fischuel Reptile Adjustable Heat Lamp with Clamp

• Brand: Fischuel
• Type: Clip On
• Dimensions:
• Watts: 25 & 50

✅ Pros:

• Affordable
• Doesn’t take up a lot of space
• Easy to attach & position
• Comes with 2 different strength bulbs
• Provides both UVA, UVB, and heat
• Fully adjustable heat control
• Great for smaller turtle tanks

❌ Cons:

• Adjustable neck tarnishes if it gets wet
• Best suited to an open-top tank
• Power chord could be longer

This clip-on UVA, UVB, and heat light for turtles by Fischuel could be just what those with a smaller open-topped turtle tank are looking for.

You could look at this as a miniature mercury vapor bulb.

The 2.95″ wide clamp holds a firm grip on the tank yet is easy to open. The 11.8″ neck is fully adjustable through 360° so can be positioned almost anywhere you like.

Comes with a 25-watt bulb and a 50-watt bulb. Both provide UVA, UVB, and heat for your turtle and are splashproof so won’t shatter if they get wet.

The adjustable controller allows you to increase or decrease the temperature of the light bulb so you can fine-tune it to your turtles’ basking area.

A couple of niggles, the power chord is only 40″ long so you may need an extension cord. The adjustable neck doesn’t have any water protective coating so may start to rust after a while. Still, not bad when you consider the low price point.

All in all a great budget-friendly choice for a smaller tank with an open-top, or one with a partly removable lid.

6. Zoo Med Reptisun 22″ 5.0 T5-HO UVB Fluorescent Bulb

• Brand: Zoo Med
• Type: Tube
• Dimensions: Length 22″ x Diameter 0.98″
• Watts: 24
• UVB Output: 5%
• UVA Output: 30%

✅ Pros:

• Energy efficient
• Quartz glass
• Full-spectrum
• Prevents metabolic bone disease

❌ Cons:

• Needs a secure light fixture inside your turtle tank or terrarium hood

You can probably tell by now, that I am a fan of Zoo Med products, and for good reason. They make high-quality 5.0 or 10.0 UVB lights for turtles and have a solid reputation for great customer service.

The Zoo Med Reptisun T5 5.0 UVB is the latest innovation in fluorescent tube technology.

Not only are they thinner so they take up less space, but they are also brighter than the T8 and T12 bulbs, and they’re a lot more energy efficient so use less power to run which is great for the environment and your utility bill.

The quartz glass tube has been engineered to offer more brightness and give maximum UVB penetration depth of up to 12″ from the bulb.

Fix these bulbs into the Zoo Med Reptisun T5 HO Terrarium Hood and you can increase the UVB penetration depth up to 20″ from this bulb!

The hood comes with this 5.0 T5-HO UVB bulb included.

7. Zoo Med Reptisun 22″ 10.0 T5-HO UVB Fluorescent Bulb

• Brand: Zoo Med
• Type: Tube
• Dimensions: Length 22″ x Diameter 0.98″
• Watts: 24
• UVB Output: 10%
• UVA Output: 30%

✅ Pros:

• Energy efficient
• Quartz glass
• Full-spectrum
• Prevents metabolic bone disease

❌ Cons:

• Needs a secure light fixture inside your turtle tank or terrarium hood

The Zoo Med Reptisun T5 10.0 UVB is the big brother to the 5.0 fluorescent tube above.

Offers you 16-18″ of UVB depth penetration as opposed to the 12″ of the 5.0 above.

Team this 10.0 bulb up with the Zoo Med Reptisun T5 HO Terrarium Hood for up to 30″ of UVB depth penetration.

8. Mega-Ray Mercury Vapor Bulb – 100 Watts (120V)

• Brand: Mega-Ray Pet Care
• Type: Mercury Vapor
• Dimensions: Height 7.5″ x Diameter 5.5″
• Watts: 100

✅ Pros:

• Longer lasting than other MVB’s
• All in one UVA, UVB, and heat source
• Safer emission of UVB
• Self-ballasted

❌ Cons:

• More expensive than other MVB’s
• Not splashproof

This 100 watt Mega-Ray mercury bulb provides UVA, UVB, and heat for your turtle, so it’s a great all-in-one solution.

It screws into standard threaded sockets without needing an extra ballast so is super easy to install.

When placed 20″ above the basking area this bulb will put its UVB down in an area of 9.5″ in diameter. If you have a mesh screen in place obviously this will affect the amount of UVB hitting that spot so you’ll need to adjust the height of your bulb accordingly.

Not the cheapest mercury vapor bulb on the market, but it lasts much longer than most others, you should get approx 2 years out of this so saves you money in the long run.

Also available in 70 watt, 160 watt, and 275 watt ratings.

A recommended shade for this bulb is the REPTI ZOO 8.5 inch Reptile Light Fixture.

9. TEKIZOO UVA UVB Super Sun Lamp (80W)

• Brand: TEKIZOO
• Type: Mercury Vapor
• Dimensions: Height 4.8″ x Diameter 3.75″
• Watts: 80

✅ Pros:

• Good price
• Self-ballasted
• All in one UVA, UVB, and heat source

❌ Cons:

• Not as durable
• Not splash proof

My 2nd mercury vapor bulb in this roundup, the Tekizoo Super Sun Lamp is a solid option if you want something at a lower price point than the Mega-Ray above, but you are compromising on quality.

All in one UVA, UVB, and heat set up to save you space.

It screws into standard threaded sockets without needing an extra ballast so is super easy to install.

Also available in 100 watts, 125 watts, and 160 watts.

Must be mounted vertically so I recommend these bulbs are used with the TEKIZOO 8.5 Inch Deep Light Dome Reptile Lamp Fixture Aluminum Optical Reflector.

If you need something to hang your lamp on there’s the TEKIZOO Reptile Lamp Stand available.

Lifespan Of UVB Bulb

The term ‘lifespan of a UVB bulb’ refers to how long the bulb will emit UVB light. They don’t burn out like a regular household bulb, but the amount of UVB emitted decreases over time. The bulb will still light up and ‘appear’ to be working.

To check the UVB level of your bulb, you can buy a Solarmeter 6.5 to measure UV levels to check if your bulbs are still emitting enough UV light.

Although the Solarmeter 6.5 is a great product, it is a little on the pricey side, so if you don’t want to shell out for that much, there is a cheaper alternative below.

The Fischuel Quick Test UVB Card comes in a pack of 2. Each card will test your bulb up to 500 times so gives you great value for money.

A rough guide for how long each bulb type will emit UVB light is below:

What Wattage Of UVB Bulb For Turtles?

Some brands of UVB bulbs come in 13 watts and 26 watts which give off the same amount of UVB light.

The difference is the 26-watt bulb is brighter than the 13-watt bulb, but, it uses more energy so will increase your utility bill.

How Far Away Should UVB Light Be From Turtle?

Ideally, your UVB bulb should be kept 10-12 inches from your turtle if there are no obstructions between them.

If your UVB bulb is too close you risk burning your turtle just like a sunbed would burn us if we stayed on it too long.

On the other hand, if your UVB lamp is too far away your turtle isn’t going to absorb enough UVB light.

The depth of UVB penetration from compact and tube bulbs depends on the bulb rating:

A mercury vapor bulb gives you 3 feet of UVB penetration regardless of which you buy. The difference between them is the higher the wattage, the more heat they give off.

What bulb is correct depends on your specific species of turtle, the size of the tank, and the type of lid if you have one, so make sure to do your research.

If you have a mesh screen on the top of your turtle tank, this is going to halve the depth that the UVB rays reach into your turtle’s tank so you would need to buy a stronger bulb.

If you have a glass lid on your turtle tank you will need to fit the UVB light inside the tank as glass blocks out 100% of UVB light.

Turtle UVB Bulb FAQ

4 frequently asked questions about turtle UVB bulbs are:

Should I Leave The UVB On At Night For Turtles?

No, you shouldn’t. Turtles need a natural daytime and nighttime routine just like we do. Unlike us, turtles are able to see UV light so if you turn your UV lights off at night, this will get them into a daytime and nighttime routine.

It’s recommended you keep your UV lights on for 10-12 hours per day.

It’s best to use a light timer so that you don’t forget to switch them off.

Can Turtles Get Too Much UVB?

Yes, they can. As I covered in this post, different ratings of bulbs give off different amounts of UVB light. Which is right for you depends on your specific species of turtle and several other factors.

Light positioning and how long you have your lights on for all play their part.

Do Turtles Need A Basking Lamp?

Yes, turtles need a basking lamp. Turtles are cold-blooded and use the environment around them to regulate their body temperature.

Turtles bask naturally in the wild so you should provide a heat lamp in their tank.

Can I Use A Regular Light Bulb?

No, you can’t as they don’t give off anywhere near enough heat or UVA light.

They’re also prone to shattering if they’re splashed with water.

For your turtles’ safety, and your own, I do not advise using a regular household bulb in your turtle tank.

Final Thoughts On The Best UVB Bulbs For Turtles…

As we’ve now established, having a UVB light for your turtle is essential for its overall health and well-being.

If you’re still undecided here’s a quick recap of the best UVB bulbs for turtles:

• Zoo Med Reptisun 10.0 UVB Mini Compact Fluorescent (Best Compact Bulb)
• Zoo Med Reptisun 22″ 10.0 T5-HO UVB Fluorescent Bulb (Best Tube Bulb)
• Mega-Ray Mercury Vapor Bulb – 100 Watts (Best Mercury Vapor Bulb)
• Zoo Med Aquatic Turtle UVB Heat Lighting Kit (Best Starter Kit)
• Fischuel Reptile Adjustable Heat Lamp with Clamp (Best Light For Smaller Tanks)

Check out the turtle section for more in-depth reviews and care guides.

For the most environmentally friendly way of disposing of your old bulbs, visit https://lamprecycle.org/en/