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lux to PAR convertion?

O. Pedersen and C. Christensen are the brain trust at Tropica so the data is probably as good as it gets. I'm guessing that this is derived from empirical measurements from a given light source and the data points plotted against each other.

Finally, a major vendor tells their fans to get off the megawatt wagon. :clap:

Cheers,
 
that's what I thought. Even if not 100% accurate, it can probably tell a rough figure which is not bad for a general assessment of our PAR measurements. I do have access to a luximeter but not a PAR meter.

cheers

GM
 
I was doing LUX equations in college yesterday and was meant to ask if there was an equation I could use to work out PAR from LUX.
You can work out the LUX fairly easy from candela (spelling) ....I think, haha. it's wrote down in my book at home ill have a look, there must be an easy way with out using a PAR metre to estimate what your getting from a luminaire rates at X amount.
 
foxfish said:
Could one of you guys abbreviate what they are saying?
It seems to me that light is emphasised as much as C02?
Click to expand...
Golly I don't look at it that way at all. In fact the very first paragraph states clearly that:
Poor growth in plant aquaria has usually been attributed to insufficient light over the tank and when asking the experts, the advice has always been to increase the light availability before any other action is taken. New research shows that this may be poor advice, in particular, for an aquarium without CO2 fertilisation.
Click to expand...
So immediately the preamble indicates a de-emphasis on light. In the three paragraphs that follow they talk about the already highly efficient light gathering mechanisms that are in place for aquatic plants which typically live in waters which are obscured by turbidity. Our tanks have gin clear water so these light gathering mechanisms get overdriven in a tank. They also discuss the concepts of Light Compensation Point )Fig 2A and CO2 Compensation Point Fig 2B.

Also, look at the Fig 3 which shows the growth rates observed with the four permutations of Light and CO2. Look at how there is very little difference between the growth rate of "low CO2 + high light" (the yellow line) versus the "high CO2 + low light" (the green line). And we know what happens with low CO2 + high light, algae, right? So if you follow the green line, the growth rate will only be slightly less but the plant health will be improved. OK, they don't explicitly state this but we've seen enough disaster movies to know that. Then, with high light, look what happens when you now combine it with high CO2. The growth rate is almost trebled compared to low CO2.

Cheers,
 
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