They don't even work well for FW Plants. Tried it in a propagation tank once, other than being ugly looking the plants grew more algae than anything. Probably because of the UV, I didn't know they produced a lot. Makes me feel great about using them as shop lights now.
Thanks Mike. I appreciate it. Hey, I know this is off the subject of lighting, but I have about 100lbs of Lava Rock and it has been sitting outside next to a house. I sparyed it off w/ a water hose pretty good. I then put in a 55 gal tank w/ two power heads, two power filters & a heater. I wanted to know if this will eventually clean the rock good enough to use for a SW tank? I plan on adding LR to this tank to try and get this lava rock full of organisms as it cycles. I will then add all this rock to a 150 gal tank.
Will I just through a reply on your question about the lava rock. A little more on the halogens. I am not sure if folks know this but most of the japanese forums of reefs do use halogens. What they do is get small ones and that are colored (usually orange, or blue) and direct them from a distance on thier corals, they UV with in the lights bring out UV pretectorant pigments in the corals and can color them up nicely. I dont recommend this to anyone however as you really walk a fine line with what is to much and what is OK, a little bit to much and you have a nice pretty white coral.