Lighting for a 120...

[jschall]

I'm planning on building a canopy when I get a 120 gallon tank.

My tank is planted with low-light plants, which are doing reasonably well under 2 t8s (64 watts) in a 75 gallon tank.
I was thinking about using cheap ($55 for a 4-tube) fixtures from a hardware store to go to 4 or 6 t8s (128w or 192w) in the 120's canopy.

Anything wrong with using these fixtures? They won't be enclosed. Will I need glass underneath them?

 

[JakeH]

If I was building a canopy I would either step it up to T5HO's or just do a bunch of screw-type sockets with 23w CFL's. Or maybe one T5HO in the middle & CFL's around the perimeter... T8's just dont have the output to justify taking up that much space in my opinion.

 

[jschall]

If I was building a canopy I would either step it up to T5HO's or just do a bunch of screw-type sockets with 23w CFL's. Or maybe one T5HO in the middle & CFL's around the perimeter... T8's just dont have the output to justify taking up that much space in my opinion.

cfls are like 60 lumens per watt. t8s are like 80 lumens per watt. I definitely don't NEED more than the 128w. Space isn't an issue, I'll have 2ft of width.
About the glass underneath them - I'll definitely need covers anyway. I'm planning on having the back of the canopy open for cooling the lighting, so for jumpy fish, heating efficiency and evaporation I'll need covers.

 

[JakeH]

There are many other factors to consider beyond lumens/watt of output, but if you prefer T8's, go for it. Many people have been growing great tanks with them for a looooong time.

 

[jschall]

There are many other factors to consider beyond lumens/watt of output, but if you prefer T8's, go for it. Many people have been growing great tanks with them for a looooong time.

I think linear fluorescents are more efficient than CFLs.