Re: Lighting and Lux

[Billinet at aol_com]

Hi, Wright,

OK, I misapplied the inverse square "law", and there are other things in an 
aquarium that interfere with the transmission of light energy, and there are 
other variables, but, darn it, it is a fact that deep tanks are noticeably 
darker at the bottom given the same watts per gallon as shallow tanks, and 
some bottom dwelling plants that do fine in shallower tanks just don't make 
it in deeper tanks.  I think we've all witnessed that.

What I would like to see would be a table that would quantify this 
difference.  It wouldn't contain "thousands" of entries.   Maybe just about 
100 cells.  In spreadsheet terms, column A would contain the distance in 
inches from the light source, perhaps at four inch increments.  Across the 
top would be the description of the light source, such as "Brand A, 20 watt, 
one tube," "Brand A, 20 watt, 2 tubes," "Brand B . . .. ," etc.  For each of 
the three or four depths the lux would be shown.

Perhaps other light source variables might be included, such as the 
efficiency of the reflector ("high" or "regular").  Not all kinds of lights 
would be need to be included.  I'd guess that no more than 100 spreadsheet 
cells would be required.

So, Wright, I'll design the spreadsheet form and e-mail it to you, and you 
can coordinate the gathering of the data.  Then as a group here we can 
estimate the lux requirements of various plants and revolutionize the hobby!

How about that?

Bill