Re: [APD] Minimum Light Threshold.....

["S. Hieber" <shieber at yahoo_com>]

One thing that might affect the situation is that more of
the light passes through the glass rather than being
relfected back into the tank because more light strikes the
glass at a less acute angle.

As for correct vs crazy -- no reason you couldn't be both
;-)

sh
--- Rex Grigg <rex at dsl-only_net> wrote:

> In the web forums I participate in the discussion has
> come up many times 
> about how much light you need on a certain size tank to
> grow plants.  Many 
> times the tank in question is a 10 gallon tank.  People
> have 20-30 watts of 
> light and are having problems with plant growth and go on
> to refer to the 
> watt per gallon rule, which while being a lousy rule does
> work for most 
> tanks but not larger or smaller tanks.  I feel this is
> due to a little 
> explored or understood "Minimum Light Threshold", the
> idea behind this is 
> that every plant requires a certain amount of light
> energy that is not 
> clearly defined in the watt per gallon rule.  Extreme
> example: We mostly 
> agree that 4 wpg on a larger tank is a lot of light.  But
> if you take a 
> gallon of water and a 4 watt light you can't grow plants.
>  Why not?  You 
> have 4 wpg.  True, but you have not met the MLT for the
> plants.  I see it 
> all the time in my terrestrial garden.  There are plants
> that do well in 
> deep shade and others that require full sun.  Light is a
> nutrient.  Some 
> plants require more of some nutrients that others.  And
> all plants need a 
> certain amount of light energy to function.  This amount
> varies from plant 
> to plant.
> 
> So now, please tell me either I'm totally nuts and should
> put the closely 
> fitted canvas jacket with the long arms back on or maybe
> I'm actually on to 
> something here.
> 
> In Heaven We were formed...
> In Hell We were trained..
> On Earth We were released...
> United States Marine Corps
> 
> Semper Fi  
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