Bleaching Crocea?

[Lockhartia]

Just a quick question/concern. I have a roughly 3" Crocea that I got last March-ish. He's been in my 55ga since then and has been doing very well! Tank params are:

Salinity: 1.25
pH: 8.1
Temp: 76
Alk: 9 (api brand test kit)
calcium: 420ppm

For lighting I run a 7x54watt aquactinics constellation. He's about 3/4 of the way up the tank in the rockwork.

Over the past few days I've noticed his mantle seems to be fading slightly, and turning more brownish than his original purple, and in spots it seems very light. I will try to get a picture but my camera is less than spectacular and my photo skills are even lower quality lol. He's still open fine and very reactive to light. The only fish in the tank is a leopard wrasse. I see no evidence of pests and his foot is good and stuck to the rock. The only thing is he's completely surrounded by mushrooms (they're like dandelions in my tank). I don't think that would have much to do with a color change?

I have four other crocea, the newest one being 6+ months old, and one 6 month old Derasa. The last thing I added to the tank were a few SPS frags about a month ago.

Any ideas what could be causing this? Should I be worried and what should I do? Thanks for any suggestions!

 

[Maximus Clammus]

How old are your lights?
Can you post a pic?

 

[Lockhartia]

Borrowing a camera from a friend today, so hopefully I"ll have them tonight. The light is only about a year old, but the bulbs were new few months ago.

BTW Salinity is realy 1.025 (what happens when you rush!)

 

[a4twenty]

as pointed out a picture is best


how old were the bulbs when you replaced them??
did you change spectrum drastically??
did you acclimate to the new lights??

 

[Lockhartia]

Here's the best pic I could get of the little guy.

Sorry my photo skills aren't all that great. You can kinda see the browning/lightening of his mantle however. Here's a FTS to give you an idea where he is. The clam in question is on the right side, about halfway up (under the seething mass of anthelia)

The light fixture and 99% of the bulbs were put on the tank last June-ish, so not even a year old. I did just replace the center bulb with a Sylvania 75/25 over a Sylvania 65K to tone down the yellowish a bit, but that was maybe two months ago? I just noticed this bleaching a few days ago. Let me know what you think!

 

[a4twenty]

from his mantle colour and apparent reaching for light i would say he needs more light. i would suggest trying to move him up slowly as to not shock him to bad.

does you fixture have individual reflectors??

 

[Lockhartia]

Yes it does.

 

[mscarpena]

I agree. Try to move him up. Also full spectrum lighting is best for clams. You said your bulbs are on the yellow side. Also you said sylvania bulbs, are those made specificly for aquarium use. If not I would try a full spectrum aqaurium use bulb.

 

[Lockhartia]

It was only one of the seven bulbs. Yes they are all specifically aquarium bulbs. Given where I work I can experiment with different bulbs with relative ease. Was trying the "grow" bulb for coral growth (which it worked fantastically) but it was just a little too "yellow" even against the six other bulbs. How, exactly now...do I move him, as he's affixed quite solidly to the rock?

 

[mscarpena]

You can sometimes cut the byssal thread, but I always reccomend moving the entire rock. The anthelia above him does not require that much light I would try switching their postions by a flip of the rock. Clams deffinately need full spectrum lighting. It also could just be a change in color due to the change in spectrum. Swap the bulb you had before and see what his color is. Everything looks slightly different under different lighting especially clams. Their hosting algae can change their orientation and it changes how the reflect light. Also high UV exposure can cause bleaching.