relationship between lighting and calcium??

Guest · Post by **Guest** » Tue Sep 05, 2006 8:13 pm

I don't know that they really hide all day in the wild. Well, what I mean is, I think they hide to avoid being eaten by something, or to stay out of the extreme temperatures, but that doesn't mean they are necessarily buried all day.

Willow · Post by **Willow** » Tue Sep 05, 2006 10:52 pm

I have noticed better general hermie health in my crabitat since I put in a Repti-Glo 8.0 UVA/UVB light. I also switched to all-natural foods at the same time, so I'm not sure if it's all due to the lights, but it can't hurt. I've seen better moults, better appetites, and fewer deaths of unknown causes.

tonycoenobita · Post by **tonycoenobita** » Wed Sep 06, 2006 12:13 am

>ReptiSun 2.0
>ReptiSun 5.0
>Nocturnal Infrared Heat Lamp
>NIGHTLIGHT RED Reptile Bulb

For the above bulb/light , can someone tell me which one should I choose?

Guest · Post by **Guest** » Wed Sep 06, 2006 12:20 am

tonycoenobita wrote:>ReptiSun 2.0
>ReptiSun 5.0
>Nocturnal Infrared Heat Lamp
>NIGHTLIGHT RED Reptile Bulb

For the above bulb/light , can someone tell me which one should I choose?

I use the Repti-Sun 2.0 for daylight & both a moonglow & a red nightlight reptile bulb for night lighting. Whether this is the correct lighting, I am not sure....but it has worked for me for some time now.

Willow · Post by **Willow** » Thu Sep 07, 2006 10:44 pm

tonycoenobita wrote:>ReptiSun 2.0
>ReptiSun 5.0
>Nocturnal Infrared Heat Lamp
>NIGHTLIGHT RED Reptile Bulb

For the above bulb/light , can someone tell me which one should I choose?

If you want UVB, you'll need to choose one of the Repti-Sun bulbs. Because most fluorescent UVB lights don't release very much UVB (no matter what they say on the package), I prefer to pick the lights with the highest posted UVB levels. So I guess I'd say, of those choices, I'd choose the Repti-Sun 5.0. I personally prefer the Repti-Glo brand (I think I read somewhere that it's better), but Repti-Sun should be fine. If you need heat lamps, the other 2 should be fine, but don't count on them for UVB.

Guest · Post by **Guest** » Fri Sep 08, 2006 8:42 am

Very good subject, now back to the research. I don't want to do anything to hurt my crabs.

Post by **JediMasterThrash** » Fri Sep 08, 2006 11:08 pm

This page:
http://www.uvguide.co.uk/fluorescenttuberesults.htm
Compares the UVB output of 8 different flourescent tubes. All of these tubes also output UVA, but that's usually not of much concern since it isn't obstructed like UVB is.

It looks like the reptiglo and reptisuns are all about equivalent.

The one that I use is a repti-glo 5.0. All of the boxes include a spectral distrubution so you can see exactly what (they claim) you are getting.

tonycoenobita · Post by **tonycoenobita** » Fri Apr 13, 2007 12:23 am

What brand or style do all of you think is the most suitable light supply for land hermit crab?

It seems that when use light, the humidity will not decrease, contrariously
it will increase?

And the light will not be too hot for them?

In fact I also want to know what is the different between UVA and UVB!?!?!

Post by **JediMasterThrash** » Fri Apr 13, 2007 4:48 pm

Lights affect humidity in two ways:

1. Increasing the heat decreases relative humidity for a given absolute humidity.

2. Increasing heat sources (such as overhead lights or under-tank-heaters) increases evaporation of water (water in water bowls or damp substrate), which increases absolute humidity.

So if the increase in heat is offset by an equal increase in absolute humidity, the relative humidity will remain the same. It's up to individual tanks and experimentation to find out how much water you have to keep in the tank, and how the tank is setup, to find this balance.

UVA is the light just after purple light. Being neares the visible, it transmits through glass well, but it prenetrates deep and can cause damage. Reptiles see UVA light like we see purple light, and use it to regulate their day/night life.

UVB is the light just after UVA. It is blocked by glass, but it penetrades deeper than UVA and causes more damage. But it also is necessary to produce vitamin D in humans and reptiles.

It is hypothesized, but there is no evidence, that hermit crabs react to UVA and UVB in a similar manner. That UVA has a role in their day/night cycle (which is why you shouldn't use a blacklight in place of a true moon-glo) and in molting, and that UVB aids them in necessary vitamin synthesis.

Lynx · Post by **Lynx** » Sun Apr 15, 2007 4:32 pm

Wow, good timing. I've been wondering about this topic lately myself! Lots of very interesting info here.

Allow me to bore you with my lengthy amateur opinions.

My personal take on the UVA/UVB subject is that we probably don't know enough about hermit crab metabolism yet to definitely know how hermies are affected by a lack of, or by an excess of, UBV. However, I think it's a reasonable hypothesis to suggest that it may be beneficial. Since the goal of crabbers is to provide our hermies with conditions as close to their natural environment as possible, I believe it's worth providing. I'm sure it wouldn't hurt to provide daytime UVA/UVB lighting, and it might help keep hermies healthy.

The lifespan of an animal in captivity whose needs are all being met properly ought to exceed its lifespan in the wild, where it gets exposed constantly to many dangers: disease, parasites, predators, starvation, etc. Most hermit crabs kept as pets have a significantly shorter lifespan in captivity (1-5 years is the average, from what I've heard) than in the wild (may reach 20-30 years?). The discrepancy suggests to me that crabbers, even though we're doing the best we can with what we know, are still missing some critical aspects of crab care.

Here are a few relevant articles from a (very useful!) reptile site I like, anapsid.org, about the importance of proper lighting in reptile health:

http://www.anapsid.org/uvtable.html - "Reptile Lighting - You may not be getting what you think you are buying."

http://www.anapsid.org/gehrman2.html - "Reptile Lighting: A Current Perspective." Has wavelength output comparison chart for several kinds of light bulb.

http://www.anapsid.org/uvd3.html - "Musings on D3 and UV."

http://www.anapsid.org/maincaptive.html#lite - the topic index

Guest · Post by **Guest** » Sun Apr 15, 2007 7:23 pm

I agree with the lighting hypothisis. I feel I seen increased health when I've provided direct access to limited UV light. Seeing is believing.

Guest · Post by **Guest** » Mon Apr 16, 2007 9:06 pm

So this means reptisun 5.0 is the best according to the chart (http://www.anapsid.org/gehrman2.html)?

tonycoenobita · Post by **tonycoenobita** » Wed Apr 25, 2007 5:43 am

May be natural sunlight is the most suitable source for them.

troppo · Post by **troppo** » Wed Apr 25, 2007 6:26 am

Yes, of course, nothing would beat the real thing Tony as long as it's practical with weather conditions

I just bought a light set up and the shop assistant(ex hermie owner

) suggested instead of buying the repti-sun bulbs that I would be better off getting what's called an Outback Max UVB 10 in 18 watts, boy does that pump out some light!

Anyway, all this stuff about the importance of UVB for hermies is new to me, but a marine biologist has said that with UVB, it helps hermit crabs metabolise something (vitamin D?) which is important for the health of their exoskeletons. He mentioned also something about how other creatures such as Australian outback lizards have similar UVB requirements, and if it's lacking then they suffer from some sort of bone disease or something.
I know this sounds fairly vague and am not sure if I'm right on this, but it was weeks ago that we had this conversation.

Willow · Post by **Willow** » Wed Apr 25, 2007 7:21 pm

Yeah, if reptiles don't get enough UVB, they'll get Metabolic Bone Disease, which causes shell deformities in turtles and tortoises, and broken bones in other reptiles, and eventually it will result in death if nothing is done to remedy it. Vitamin D3 supplements can help, but are a poor second to actual UVB exposure. Of course, natural sunlight is the best---1/2 hour a week of direct, unfiltered sunlight exposure is usually considered sufficient---but that's impossible to provide all the time around here, where the temps are below 50 for most of the year. I have Russian tortoises, and they shouldn't be outside if it's below 50....hermies need it warmer---at least 68. I have a Repti-Glo 8.0 on both the tortoise enclosure and the 75g hermie tank. I don't have one for the 55g hermie tank yet.