HCA: Hermit Crab Association

I'm still in the process of trying to set up my crabitat and making sure everything is just right! the only thing i really need to figure out is the lighting. It's quite hard to find information about hermit crabs and UVB scattered across this forum. Some swear it does nothing at all, others say they see a lot of increased activity! I'm currently leaning towards having them, there don't seem to be that many cons and i want my crabs to live as naturally as possible. So having some sunlight makes sense! TLDR; I'm curious if those of you out there using UVB use t5 or t8 bulbs and why? I don't want to invest in lights that are to strong and possibly burn them/their eyes. Any resources you might have would also be greatly appreciated!!

I have UVB on all of my crabitats, I use Reptisun T5-HO bulbs on mine. I swear by increased activity, and happy healthy crabs. My crabs breed also. The reason I originally purchased UVB was to replicate their natural environment. Straws have to have it though

GotButterflies wrote: ↑

Sat Jul 20, 2019 1:08 am

I have UVB on all of my crabitats, I use Reptisun T5-HO bulbs on mine. I swear by increased activity, and happy healthy crabs. My crabs breed also. The reason I originally purchased UVB was to replicate their natural environment. Straws have to have it though

I'm nervous about buying the wrong thing (they're not the most budget friendly) If i buy the zoomed hood+light for my 29 gal (it's about 18 inches tall) would that be to close? On a side note I've actually seen some of your posts about zoea, they're amazing!

If you go on Amazon, you used to be able to purchase the hood and it came with the light. Then from there you purchase new bulbs every 6 months The light will still work, but the UVB won't be any good

Edit: Thank you

For the price, Arcadia bulbs work better since they are proven to last a full year. The other brands are supposed to, but most reptile keepers recommend replacing every 6 months. The T5 bulbs are interchangeable when you have the matching fixture. The Arcadia are a little stronger, so a 6% would be good for them.

I actually don't have UVB on my hermits, and mine have bred every year for the last 8 years. I do think it's a nice addition if you can, but it's not a must if money is tight.

wodesorel wrote: ↑

Mon Jul 22, 2019 2:08 am

For the price, Arcadia bulbs work better since they are proven to last a full year. The other brands are supposed to, but most reptile keepers recommend replacing every 6 months. The T5 bulbs are interchangeable when you have the matching fixture. The Arcadia are a little stronger, so a 6% would be good for them.

I actually don't have UVB on my hermits, and mine have bred every year for the last 8 years. I do think it's a nice addition if you can, but it's not a must if money is tight.

So something like this would be good? https://www.reptilebasics.com/arcadia-f ... 5-bulb-22/
Edit: The Arcadia hoods are quite a bit more expensive then the Zoomed ones could I put an Arcadia bulb in a Zoomed fixture?

Yes and yes! I originally bought the zoomed set for my turtles, had problems with the bulbs not producing UVB, and then invested in the Arcadia bulbs during that same store's Black Friday sale.

wodesorel wrote: ↑

Mon Jul 22, 2019 7:13 am

Yes and yes! I originally bought the zoomed set for my turtles, had problems with the bulbs not producing UVB, and then invested in the Arcadia bulbs during that same store's Black Friday sale.

Okay awesome! Thanks so much you've been super helpful! How do you know when bulbs aren't producing UVB anymore?

The HermitIX wrote: ↑

Mon Jul 22, 2019 1:57 pm

Okay awesome! Thanks so much you've been super helpful! How do you know when bulbs aren't producing UVB anymore?

You can't, unless you have an expensive (around $225) meter to check for UVB output. That's why the bulbs need replaced on a set schedule for safety, as testing has shown 6 months to be a good period for normal brands, and 12 months for Arcadia. In hermits, it's not deadly for them not to have it thankfully! For reptiles who need it, going without for just a couple months can cause permanent deformities and death, so it's not worth taking the chance.

wodesorel wrote: You can't, unless you have an expensive (around $225) meter to check for UVB output. That's why the bulbs need replaced on a set schedule for safety, as testing has shown 6 months to be a good period for normal brands, and 12 months for Arcadia. In hermits, it's not deadly for them not to have it thankfully! For reptiles who need it, going without for just a couple months can cause permanent deformities and death, so it's not worth taking the chance.

That’s awesome! Thank you for the information and the explanation behind these things. My inquiring mind always likes to know these things! So thank you to you both, now I’ll know what to watch for when I get one in the near-ish future.


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