Crocea mantle question

[Reefmongrel]

I have 3 clams in my 90. Derasa, Crocea, and Teardrop maxima. Water parameters are Ca 400, dKh 9, nitrates 0, temp 80, SG 1.027. lighting consists of 2-250W Halides, and 2 - 54 watt T5s.

The Crocea has been about 15 inches from the halides. I have noticed that the mantle on the Crocea has thickened, is questionably bleaching, and it is a bit less 'electric' in color than when new. It remains very reactive. The other 2 clams are fine. No snails in site.

What is the Crocea trying to tell me? Too much light? Water params?

Any thoughts appreciated.

reefmongrel

 

[mbbuna]

what K bulbs do you have?

 

[Reefmongrel]

Bulbs are Ushios 20K.

 

[fishieness]

20000K bulbs do not have as high a par as a lesser K rating. plus they dont have the wide spectrum needed. it is possible that they are not getting enough light. esspecialy if they are SE.

 

[Reefmongrel]

Sorry - they are 10K Ushios.