LUX Meter...

[spw4949]

I just have a few questions, what is a good reasonably priced lux meter & as far as actually measuring light in our aquariums I'm assuming that you submerge the meter in the water? Sorry if that seems like a stupid question but I'm new to world of lux meters & am trying to gain a better understanding.....thanks in advance.

[spw4949]

Ttt........

[10001110101]

http://www.specmeters.com/Light_Meters/Quantum_Light_Meter.html

that's what you want. a PAR meter, measures light in photosynthetically active light spectrum, so basically light that is usable for photosynthesis by zooxanthellae.

a lux meter is pretty much useless as it relates to brightness to the human eye, not to wavelengths usable to photosynthesis.

a PAR meter is really not even truly accurate, as corals and their symbiotic algae have adapted to a bluer light spectrum, so are more able to use the blue end of the spectrum than land plants... but a PAR meter is the closest you're going to get and works fine for making relative comparisons

[Dave71]

I would suggest you read

http://www.advancedaquarist.com/2005/7/review/view?searchterm=None

Apogee makes the unit most consider the best for aquarium enthusiasts at an affordable price.

You want to make sure you are using the water proof sensor, as the unit itself is not.

[wayne in norway]

If you do buy a lux meter then get the cheapest you can - the cheapos don't do any weighting of the various parts of the spectra so the relationship between LUX and PAR becomes a straight line function. You'll need to calibrate it with a PAR meter tho, and get the function LUX = X PAR