lighting question

[Krunchy the krown]

Since acrylic tanks are mostly covered, with small openings on top, my
question is this

Will anything beneficial from the lights be blocked by the acrylic? E.G. ,
when lighting reptile enclosures glass or screen tops will reduce the
effectiveness of beneficial UV rays. Will the same thing apply to acrylic
tops and lighting with a reef tank?

[Captain Feedback]

Here's a reply to a similar question asked a while back:

Glass typically transmits approx 80% +/- of the visible spectrum
(400-700nm)
Acrylic typically transmits approx 92% +/- of the visible spectrum
(400-700nm)
Glass typically "filters" approx 90% +/- of utraviolet (<400 nm)
Acrylic typically "filters" approx 95% +/- of ultraviolet (<400 nm)

These numbers are "generalities" between plain ol' plate glass and cast
acrylic
(non-specific mfrs)
There are also some color variations based on the nature of each mfr,
grade,
and batch, ie.,, glass has a slight green hue which will vary and these

variations will affect light transmittal to some degree, and different
acrylics
made by different mfrs also have some color but a complete comparison
would be
prohibitive
Of course there are special grades of both that transmit or filter
different
wavelengths for different applications. When you get to longer
wavelengths
(>700 nm) they do a coupla switchbacks as far as transmission goes
but...
If you need more info, lemme know.

[Krunchy the krown]

"Captain Feedback" > wrote in message
ups.com...
> Here's a reply to a similar question asked a while back:
>
> Glass typically "filters" approx 90% +/- of utraviolet (<400 nm)
> Acrylic typically "filters" approx 95% +/- of ultraviolet (<400 nm)
>

Is the lack of exposure to the lower end of the spectrum(<400 nm ) going to
have an adverse effect on SPS,LPS or anemopnes?

I understand that the upper band(>400 nm) is essential to their well being,
but is the lack of the lower band ( <400 nm) detrimental?