Re: Best fluorescent tubes? (2x20 watt PlenPlax)

["Bill Wichers" <billw at waveform_net>]

>I just installed two standard PlenPlax 20 watt ($13.99 US) bulbs into my
>newly set up 55 gal tall planted tank (they claim accelerated plant growth
>with no algae stimulation!)  Running them about 16 hours a day.
>Is this an okay amount of lighting?  And and okay brand/type?

16 hours is a bit long of a light cycle. Remember that aquarium plants are 
generally expecting tropical or sub-tropical lighting conditions, which 
tends to be about 12-14 hours per day. 

You don't mention specifically what kind of bulb you're using so it is 
difficult to comment on it, although I can assure you that it WILL grow 
algae just about as well as it will grow your plants. I think 40 watts over 
a 55 gallon tank is running pretty low. I use 55 watts of PCF lighting over 
a 20H tank, and would suspect that two such fixtures would be about the 
minimum you'd want over a 55 gallon tank to ensure good plant growth. 

I suspect that you are using the standard hood that can be purchased for a 
55 gallon tank. Few such hoods are capable of running suffcient lights for a 
planted tank. You can find a few (like All Glass's new Power Compact 
Flourescent (PCF) hoods), but usually people either build their own custom 
hoods or retrofit commercial hoods using kits like those sold by AH Supply 
(http://www.ahsupply.com). 

    -Bill 

*****************************
Waveform Technology
UNIX Systems Administrator