Quote:
Originally Posted by
DrewsBrews http:///forum/thread/377726/light-question-help#post_3325293
oah well that sucks.
I know you guys are referring to Halide to use for clams but why does everyone always seem so down on PCs and up on T5? I figure they are both flourescent tubes so watt for watt wouldn't output be similar?
You can keep clams under T5's as well, even PC's is possible, but it all depends on the PAR. A 100 watts of PC lighting produces less than 100 watts of T5, which produces less than 100 watts of Halides. I'm not a lighting expert, but basically it has to do with how the lighting is able to travel through the water and how far it is still effective.
PC's are really only good for fish only and soft coral tanks. They just do not provide enough light for many corals. Keep in mind that most corals have algae living inside of them (zooanthellae) that keeps the coral healthy. This algae, like any algae is photosynthetic, and needs the strong lighting to keep it healthy. If the coral is not provided with strong lighting, it will release the algae and die. The same is true about colorful clams, they feed off the light. PC lighting is not as much like natural sunlight as T5 and halides are.
You also need to remember that most reefs are fairly shallow, so sunlight can really travel through the water to reach all the organisms that require it to survive.
PC's work fine for fresh water setups and fish only setups, because the sunlight requirements are much less.
If you plan on keeping most corals or clams, you're going to need a good T5 setup or metal halides.