Clams stopped growing

[Rockster2599]

Hi All,
Initially my clams were growing but the growth has slowed almost to nothing. I haven't seen any pests so I'm assuming they aren't getting enough light?
The lack of growth seems more pronounced since I have switched to my Kessil A350w. I used to have twin par 38 which weren't great because they had a powerful cone of light however this was working as the clams were in the sweet spot despite the fact they bleached a lot of my LPS. Do you think the light is the main suspect?
I have recently ramped my Kessil up to 100% and raised my clams as high as possible. I haven't noticed any pyramids or other pests.
What do you guys think, I would hate for the clams to die.

[jda]

How are the water parameters? Enough calcium and alk?

How long have you had them? How long were they under each kind of light?

[moliken]

pics? maybe a calcium reactor

[AquaTDV]

Check your phosphate levels...Whenever I see slow clam growth and my Ca and Alk levels are in line it is usually because of elevated phosphate levels above .07.

[Rockster2599]

I've had my crocea for 4 months, and my maxima for 10 months and I think they were growing until a couple of months ago.
This weeks tests were:-
Sg1.025
pH 8
Kh 9.6
Mg 1260
Ca 420
NO3 0.5
PO4 0.06
They may have fluctuated a bit over the months but they are around that level.
They were under the PAR38s until January, so the crocea was always under the Kessil.

[Rockster2599]

It like they were growing when the Kessil went in but then the growing petered out and stopped.

[Rockster2599]

Bump for an answer before I sell a kidney for a lighting upgrade:lmao:
Here is a pic with a bonus blenny.

http://www.ultimatereef.net/uploader/2013Q2/reeferblenny_1.jpg

Crocea on the left, maxima on the right. I picked up the small maxima over the weekend but it was way smaller than I thought when I ordered it (online).

[jda]

They look OK, but they nearly always do right up until they die. If you are a Kessil guy, then stay with it and see what happens.

[Rockster2599]

They look OK, but they nearly always do right up until they die. If you are a Kessil guy, then stay with it and see what happens.

Not massively re-assuring:lol: but I do love my Kessil.
Any other opinions?

[OrionN]

You have algae, likely phosphate problem. Test kits for phosphate is not accurate. Try increase water change to get the phos down. Light seem OK from the way the clamsopen up. In low light the clams often hyperextended a lot for a while, loose color then died.

[Rockster2599]

Thanks Minh,
The Algae situation isnt ideal but over the last 2 weeks I have been switching from carbon dosing to an algae scrubber and absorber but obviously havent quite got the balance right. I am using a Merck kit which I thought was fairly accurate but do feed heavy due to my many LPS, I cant really up water change frequency as I do daily water changes:eek1:.
Ill cut back on my feeding.
Nice to know that you think the clams look like they arent hyperextending. Might save my wallet yet:dance:

[michika]

Can you just confirm the time lines I think I'm reading?

"I've had my crocea for 4 months, and my maxima for 10 months and I think they were growing until a couple of months ago."

So they've both completely stopped growing, pushing out a new free edge of their shell?

I've kept all sorts of clams for almost a decade now and they're a lot like some plants; they have a period within the year where they're growth is reduced, sometimes they grow so little you can barely tell, and sometimes they just slow down. Clams can also be disrupted by other ongoings in your tank; changes in dosing regimens, new salt mix, etc.

Maybe try taking some photos from the same location weekly to give yourself a measurable reference tool to look back on.

[Rockster2599]

Can you just confirm the time lines I think I'm reading?

"I've had my crocea for 4 months, and my maxima for 10 months and I think they were growing until a couple of months ago."

So they've both completely stopped growing, pushing out a new free edge of their shell?

I've kept all sorts of clams for almost a decade now and they're a lot like some plants; they have a period within the year where they're growth is reduced, sometimes they grow so little you can barely tell, and sometimes they just slow down. Clams can also be disrupted by other ongoings in your tank; changes in dosing regimens, new salt mix, etc.

Maybe try taking some photos from the same location weekly to give yourself a measurable reference tool to look back on.

Those are the correct timelines and yes they have both stopped growing. Thanks for the advice, I'll try to keep everything stable and watch them for a while. Thanks:thumbsup: