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

Re: Osram Dulux L 2G11, 55W/21-840



> I am guessing that they are 840 phosphor
>  lamps which means they are thick coat
>  high CRI 4000 K lamps. If so, they are
>  more yellow than most people like but
>  that is up to your personal taste. It
>  does not mean they will not grow plants
>  though.

I'm using General Electric SPX41 lamps, and plants love them.  I'll relamp 
with SPX50's when these wear out, but you get use to the yellower color if 
you do not have a lot of floating plants right under the lamp.  When my tank 
starts to look dingy, I trim tall plants a little and thin out the duckweed.  
I've also found that the 4100K lamps look sparkling white after I polish the 
water with a diatom filter.  So, some of the yellowish cast is due to 
suspended particles and algae scattering the light.

FWIW, I use SPX35 lamps as "grow lights" for starting seedlings in the winter 
and the terrestrial plants grow great.

best regards,
bob