Re: Lighting for a paludarium

[Bill Wichers <billw at waveform_net>]

>I am considering setting up a 55 gal. tank as a paludarium, and am
>wondering about lighting.
>
>1.  Because the water surface will be farther from the light source than
>in an aquarium, it seems that there should be a lot more reflection of
>light at the water surface.  What kind of generalizations are used to
>determine how much light it would need for a medium to high-light
>situation?

I would assume you will need lighting somewhat similar to that used for 
open-top tanks where the lighting is suspended some distance above the 
water surface. In most cases this will give you enough room to use good 
reflectors though, and good reflectors help to direct more light into the 
water. I think you will also need to consider the fact that the 
exposed-to-air portion of your paludarium will be getting blasted by gobs 
of light if you use incredibly beefy light fixtures over the setup. To 
start, I think you'd be best off using lighting similar to what you'd use 
in a normal aquarium, but with good reflectors (Miro, Spiderlight, etc.). 
It will probably be easier to add more light if you need it rather than to 
correct problems caused by too much light.

>2.  I have seen aquarium hoods for 55's that use 24" inch lights and
>others that use 48" lights.  What are the pro's and con's of these two
>styles.

48" bulbs are probably the cheapest on the market since that is the 
standard length that is used in incredible quantities commercially. Any of 
the good GE or Phillips bulbs that you see recommended on this list from 
time to time in lighting discussions that include T8s mention these (things 
like SPX50 and such). A 48" will also provide even illumination over a 
nearly 48" wide section of tank while a pair of 24 inchers will have a 
shadowy area in the middle where the additional pair of bulb sockets will 
be. If you have a choice of 24 or 48 inch I'd go with the 48 inch.

Using T8 lights I think you'll have to use a DIY hood to get enough light. 
I doubt you could fit more than maybe two 48" T8 bulbs into a normal 55g 
hood's light bar.

>3.  Because the hoods that come with aquaria do not usually provide
>adequate light, would I be better off to make my own rather than buying
>and retrofitting?

Probably, but depends on how much light you think you are going to be needing.

>4.  Would there be an advantage to using compact fluorescent lighting
>instead of regular fluorescents?

Yes, and it involves your question (1). If you need to blast more light 
farther, it will be easier if you are using a high intensity light source 
rather than a more diffuse light source. PCF lights, for example, provide 
more light in a smaller space than do regular T8 lights. This will make 
reflector design and hood design easier.

A pair of 55w PCF lights with good reflectors is probably a good start. If 
you find you need more light you could add another pair of 55w lights, but 
that will definitely put you into DIY territory for you hood. I know that 
you can retrofit a standard 55g hood to accept a pair of 55w PCF fixtures, 
but for a second pair you will need to modify the hood in some way to allow 
the addition of what amounts to a second light bar. If you use two pairs 
you could use two timers and have a night/dawn/day/dusk/night light cycle 
with a 0/2/4/2/0 number of fixtures "on" at one time, but maintaining even 
lighting along the length of the tank.

         -Bill

>TIA
>
>Cheri
>


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