Victor,

Your comparing two different things here. Coral pigment is different then algae pigment. What was stated in my above post was the effect of blue light on zooxanthallae not coral pigment. Which is a whole nother issue that is not well understood. The type and intensity of light will cause different shades of brown in the coral do to how the zooxanthallae react to the given light. This is why people with low light reefs seem to have darker corals then those with higher lighting. I know other things play a part as well but we are talking lighting here, so I'll stick with that. I'm sure we all agree no matter what you do with your lighting you won't pull purples out of a toadstool. I suppose that the purple monster your refering to could very well be happy or healthly wether it's brown or purple. What does matter though is that it has a healthy zooxanthallae population to feed the coral in question. And IMO if the PM was in good health and growing it would have no chose but to be purple.


Also I think an Iwasaki has a much larger spike in blue light then a 5500k.

Perhaps I'm getting lost in my opinion of coral health through appearance and growth rate. Because corals don't speak I have no other judge. I do feel that the health of the zooxanthallae through reproduction and byproducts determin the health of the coral. So healthy and growing zoox=healthy and growing coral. Do corals need to grow I'm not sure. I would assume though that in the wild they would disappear with so many predators if the did not grow. Whats a healthy growth rate? I'm not totally sure.


Bob's thought was all the corals need as far as spectrum would be in a 5500k bulb. I geuss I would agree with that. As its been done and is being done. Is it the best? IMO no but I geuss I wasn't asked that.

I know we are beating this to death, but I feel that we may not be understanding what I am saying.

My point is that when the sun shines on the water the coral "sees" blue.
When you put a full spectrum bulb over the water the coral "sees" blue
When you put a blue bulb over the water the coral "sees"blue

The above statement refer to deep water. :)