I found this in a post from John Fletcher:

"Also what kind of light do you have on your tank.  If you want the yellow to be bright and not yellow-brown in the yellow polys, you will need good lighting."

My question to John or anyone is this:

When you say good lighting are you talking about intensity, color temperature or both?

I got my yellow polyps from Suzy and they are the brightest yellow I can imagine.  And I gave some of them to my friend and his have turned deep brownish-yellow.  I have 2x32 watts PC 10K/actinic over my 18 gallon, and he has 4x110 watt VHO (1 daylight and 3 50/50)  I thought the reason may be the combination of bulbs he is running.  I told him to get 2 day light and 2 03actinic but the people at The Aquarium either recommended that combo or that is all they had in stock.

Also, yellow polyps are non-photosynthetic right?  So the pigment they have is just reacting to the amout of UV light just like happens with our skin, correct?

Sorry for the lengthy post,

Dave

I think that he has had his tank up for about 4 months.  His tank is a 55 gallon and the polyps are about 1/2 to 2/3 up the water column as well. 

Thanks

Yellow Polyps are a type of anemone.  They do go through photosynthesis, but not to the extent of most other corals.  As you said Dave feeding seems to be more important.  I would be inclined to say that the polyps color is not all that important.  If they look good, and extend, and grow that is the important part. 

Here is how I look at it.  If I put a blue light (like that demonstrated last meeting) over my little tank, my anemone glows green.  Really green.  But without it he looks very white.  The way it "looks" to us may very with the differing lights on the tank, but the anemone is still the same.  If the polyps in your friends tank look healthy, then don't worry about it.

hope this helps,

Adam 

Yes My Polyps are healthy....(a little brown however)

I cant believe you people are talking about MY Polyps like this behind my back.......

What do you mean behind your back, Dave is your friend.  :)  I feel the light intensity has a lot to do with it.  At the Aquarium in Sandy, Brad had two colonies of yellow polyps.  One under his MH and the other under his VHO, the one under the MH was a yellow as could be, the one under the VHO was yellow-brown and it was at the bottom of the tank also.  He feed them and also the MH ones were in a high flow area, I don't know if that has anything to do with it.

John "ReefAquarist"

I also have the bright yellow polyps from Suzy. Thanks Suzy!!!

By the way, what are you doing to these things to get them so yellow...