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

Re: substrate heating and lighting



On Tue, May 07, 2002 at 01:22:12PM -0700, Roxanne Bittman wrote:
> Question 2 (Lighting):
> >>>The generally accepted figure for a normal planted tank is 2-4watts
> 
> (depending on plant selection, aquarium depth etc). This figure seems
> to be 
> only pertinent to fl?
> a) What are the generally accepted figure for those using metal
> halides? Do 
> I have enough? I am planning to keep a mixture of fast (e.g. hygros)
> and 
> slower growing plants (e.g. anubias sp. Java ferns) in various regions
> of 
> the tank.>>>
> 
> With even some high light plants, you will need more than 2 watts/gal
> to get good growth.  I don't know the calculation for halides, but I'm
> sure it's not like that for fluorescents.  I believe the 2-4watts/gal
> only apply to standard fluorescents.  Those of us using power compact
> fluorescent lights certainly often brighten our tanks with more than 4
> watts/gal.  Hopefully, someone who has used metal halides can answer the
> "is it enough?" part of the question.

Well, I'm not an expert, but I also keep a reef tank, which is much
more picky about light.  In comparison planted tanks are a breeze.

Metal Halide are generally considered better than floursent.  But
you don't get any more watts per gallon out of them (neither do
you out of compact flouresents versus regular floursent tubes, a
common miscomprehension).  You get a much better coverage of the
spectrum, and MH has the ability to reach deeper depths than
floursesent lights.

That's one of the reasons I decided to go with a MH pendant for my
24" high cube tank, I wanted to be able to keep high light groundcover
plants like glosso.

But the general consensus for planted tanks seems to be that MH is
overkill, and CF is cheaper (for the initial outlay, although it's
more expensive for bulb replacements).  No difference in WPG
calculations.

-Eric