Not as Happy as a Clam anymore.....

[affonsj]

have a 26 gallon nano with a crocea (2) actually.
The first I have had for a little under a year. Over the last month or so, the mantle has shrunk and it seems now the mantle is not opening.

I have compact florescents. Is this slow starvation? I have done and checked the usual tests and water changes....

The clam in question is one the bottom middle section. Now it looks like this..(second pic)-bottom center of picture

 

[Snowboarda42]

how old are the lights? They might need to be replaced.

 

[affonsj]

The lights are 3.5 years old now....
I just bought a sunpod MH fixture today

 

[Unarce]

Do you mean the fixture is 3.5 years old, or the bulbs?

Glad you picked up the Sunpod. Crocea will, most of the time, require MH or T5 lighting to thrive long-term, as they are found at the shallowest depths among all Tridacnas.

Every once in awhile, you'll hear of one that's been under PC for 3 years or more. However, these more robust specimens are the exception to the rule.

Although, I do feel that the lighting situation was the culprit here, it could very well be any number of other things. There are a lot of unknown ailments and diseases that the hobby is not yet aware of. A clam could look perfectly healthy for months, but is already on a slow decline internally. When it dies, the deterioration is only visible, a day or two before.

 

[affonsj]

Hello and thanks for the reply

The lights are 3.5 years old (I started the tank 3.5 years ago).
You are right about a multifactorial cause, however I do think its the lighting.
The clam did very well for a year with maximum opening of its mantle, however over the past month the mantle seemed to be of reduced size. I also reduced the photoperiod to 7 hours which also did not help.

I am being very careful with the second one I have which was bought two months ago and getting the MH. I perform two 5 gallon water changes a month on the 26 gallon tank (effective volume I would say is 20 gallons)

Regards

Mario

 

[oldgrayhair]

For future reference, usually a smart idea to replace PC bulbs every 6 months....or at least once a year.