UV rays

[Pussygalore]

I looked up UV rays on the internet and there is conflicting opiniums as to whether they can pass through glass, (my torts are in my greenhouse) there is a lot of in depth advice but some say that they can and others that they can't. Please tell me why things such as frogs, fish and the plants themselves can live quite happily and yet it is said to be no good for torts. If I,m right UVA rays can pass through and UVB do but at a much slower rate and it seems to depend on the thickness and type of glass. I have my door,vents and windows open and think that my torts get enough certainly when the sun is out for such a long time.

[Becks]

hi there uvb is blocked by glass and uva does pass though but not enough for ur torts needs ..
if you can let the little fellas out for a walk round the garden .. most torts need uv as its there main source of d3
UVB is used by the body to metabolize the calcium and D3 to help grow strong shells and bones.
hope this is some help but im sure some 1 who knows more than i will be along to help you soon
luv becks xxxxxxxxxxxxxxxx

[carl20]

99% of uv is absorbed by glass. uva can pass through a bit but this doesnt help a tort produce d3 it only regulates their mood.
uvb can pass through quartz glass so if ever planning building an outdoor enclosure with glass use quartz.
i dont think plants and frogs need uv very much and fish probably dont either. torts need it for their bones and shell because they are herbivors.

The uv is absorbed by the electrons in the molecules of the glass.

[sandy]

Most experienced keepers know that glass blocks the UV. But if tortoises have acsses to the outside
enclosure around the GH its not a problem. Even on dull days the UV light outside is far supiorior to
that of any artificial lights we provide.
There is a polycarbonate being tested now, that will allow the UV in. From Germany I think.