[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

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



At 23:09 9/30/2004, you wrote:
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.


I'm not talking about incandescent light. I'm talking fluorescent light. Take that gallon tank. Put a 7 watt CF light over it. You now have 7 wpg. But you will still have a very hard time growing any of the "high light" plants in it. If you want to know why I think a 10 gallon needs more light than a larger tank then read my threads over at The Planted Tank. I think I have covered it pretty well there. But to make is simple I feel there is a minimum amount of light needed by plants that is NOT covered in the watts per gallon rule as my one gallon tank example shows. And to look at it on the other end if you have a very large tank you can have 2 wpg and grow any plant. Why? Because you have crossed the minimum light threshold for that plant even though the wpg rule shows you having a low light tank.

Your example fails here and in the other forum because you seem to think the
watts per gallon rule applies to incadescent light bulbs. I presume you are
not talking about a four watt flourescent. A flourescent light is several
times more intense than an incadescent.  That is why a 13 watt screw in PC
takes the place of a 75 watt incadescent.  2 to 3 watts of flourescent light
per gallon of water over a ten gallon tank is more than enough to grow just
about anything.  A ten gallon tank is very shallow. Explain to me why a ten
gallon tank  would need more intensive light than a 20 gallon tall tank.
Please.

Robert Hudson
www.aquabotanic.com
90 day guarantee on plants!!

_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo.cgi/aquatic-plants

In Heaven We were formed... In Hell We were trained.. On Earth We were released... United States Marine Corps

Semper Fi _______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo.cgi/aquatic-plants