So just as a figure, you are saying that plants can use carbon dioxide
without any light?

Even at one watt per gallon, you can overbear your fish with carbon dioxide
levels if there isn't enough light for the plants to perform photosynthesis.

Algae is an unfortunate side effect of having light, and every tank has some
sort of algae.

I have about 2 watts per gallon on my 29 gallon aquarium (one 65 watt
compact fluorescent bulb) and I am also putting in Co2 using the yeast
method, and I still have trouble with algae.

Brian S.

"Happy'Cam'per" wrote in message
...

I would MOST DEFINITELY take Tom's advice, you WANT the co2 first, light
is
secondary.
--
**So long, and thanks for all the fish!**

" wrote in message
om...
"Spyder2x" wrote in message
news:3gidd.50272$hj.29843@fed1read07...
Hello all,

I am wanting to add both a pressurized CO2 and a
nice
lighting system. My question though is which one should I add first?
I
currently have a DIY CO2, and around 100 watts of flourescent lights
over a
135 U.S. Gal tank. The lights will be Metal Halide (these are ok for
plants
right?) Thanks for any help.


--Jim--

CO2.
Even at low light, your plant gain by having the maximum amount of CO2
to drive Carbon fixation, thus getting the most out of the available
light.

If you add lots of light first, you will get algae unless your CO2
system can keep up with it.

If you look around(see Dlink's page for CO2 systems, add a needle
valve though), you can find some cheap systems.

DIY MHs are also popular depending on your skills.

You'll need 3 x 150w or 175 w for a decent spread on a 135 gal

You will also be comfortable with CO2 before trying to run things at
high light.

Lights are pretth easy to learn how to yuse, turn on for 11 hours etc
then turn off for 13.

Not much to it.

CO2? You need to dail in a decent amount with low light now, then when
you add more light(then you have more CO2 uptake as well) you'll
already have a good feel how to adjust your system and this approach
to adding the CO2 first will minimize chance of algal blooms.

Regards,
Tom Barr