How many par 38 bulbs?

[Matthias7]

I am getting ready to set up a refugium that will contain several types of macros and possible some mangroves. The tank is a 40 gallon breeder would I need 2 par 38 bulbs over it or could I get away with one?

 

[Reefing Madness]

 

[WetWhistle]

I actually just use a Philips energy saver 100 watt equivalent with a clamp on light. I run two and my mangroves and Macro algae grow fast under them. Pick something around the 6500 to 7500 k range for best growth.

 

[Downbeach]

I had two 100W CFL's @ 6,500K on a 40, when I used a fuge. Was good for Chaeto, Caulerpa and Agar.

 

[WetWhistle]

Very cheap way of growing algae and mangroves. I grab the 4 pack of bulbs and change mine every 8 months or so.

 

[vic67]

I believe you would need two for full coverage but you can get away with one. With 90 degree optics I think the coverage is about 18"x 18"; you would have to keep macro algae under it.

 

[Matthias7]

My other option is a led value fixture that is full spectrum but the blue LEDs are no longer functioning. I would imagine it would make a good fuge light with the blues?