low flow for clams

[Stevenliu9]

Just wonder what's everyone's opinion on water flow for clams in general?
I have mix reef so it's tricky since some coral like strong flow.
But recently I experimented some intermittent "no flow" or "low flow" periods in my tank to see how my clams would do. It is the first time I have tried this and I observed that my clams appear to be extending their mantles wider than ever.
What water flow do you use for your clams?

 

[laga77]

My clams are happier with the higher flow.

 

[MondoBongo]

for at least the two that i keep, T. derasa and T. crocea, i've found them to be tolerant of a wide range of flow patterns and intensities.

the crocea specifically can be placed in a fairly high flow area. which makes sense, given where they are typically found on the reef. as long as his mantle is not actively being folded over by the current, he seems pretty happy.

my derasa, just by nature of being a lower-level, bottom dwelling type, seems to prefer much less flow than the crocea. where i had him in my old tank was one of the lower flow spots, where he is in the new tank is what i would consider medium flow. enough to let a Euphyllia's tentacles comfortably waft on the current.

to your point about the amount of openness of the clam: i've never really determined if more open is better, i.e. more relaxed, than less open. obviously too open or too closed can indicate a problem, but i've never been too certain on the inbetween.

 

[Gagonzalez]

I thought clams extend or retract their mantle based on light requirements, not flow. If they need more light, they extend more. Too much extension is not good since that means they are trying to get as much light as possible and may be starving for light.

Flow only matters if it keeps them from getting their mantle out far enough to get enough light. Hence, Crocea's get the most light in shallow waters but also the most turbulent flow normally IMO.

 

[laga77]

If I have a problem with a tank, the first thing I notice is the clams retract their mantles.

 

[Stevenliu9]

I tend to compare the clam extension to those reef diving images. And many of the magnificent looking clams seem "relaxed" with their mantled extending well beyond the edges, even those maxima in the shallow. I guess I should have specified the clams I have are derasa and squamosa, wondering if they do prefer lower flow than shallow water clams like squamosa and corcea.

 

[Coralreefer1]

Clams don't like very strong laminar flow!