Maxima Clam siphon/mouth gaping??

TViquez · Mar 19, 2024

I recently added a 3in or so Maxima clam to my 2 year old reef tank the end of January. It's always had it's mantle extended, nice coloring and very responsive to shadow. I've placed it at the top middle of my 40g cube because I only have one Kessil A80. It's about a foot or so from the surface. The last couple of days I've noticed the siphon looks very wide so I was trying to research and didn't find it very reassuring. There's nice growth on the valve/shell (?)

I've been in the hobby for 12 years so I don't really test parameters much anymore. But here they are(API, I know it's not the best but budget wise, I can't do more advanced):
This is also 8 days after water change.

Cal 440
Phos 0.5ppm
KH 11
Salinity 1.024(fluctuates to 1.025 sometimes)
PH 8.2(this was a nice surprise since it's always been about 7.8)
Nitrate 0(another surprise bc it's normally in the teens but I'm assuming it's now 0 because of my clam addition)

I also have a mini refugium in the back of my AIO with lights on that running overnight.

All other LPS corals are looking fantastic. I guess I'll increase feeding and maybe do reef roids and phyto feast daily since Nitrates are now 0.

I just want to be successful with clam keeping since I've waited a long time to get one.
Pictures included with a snap of the overall tank.

OrionN · Mar 19, 2024

That clam looks very healthy to me. No problem I can see. gaping of the clams would show retraction of the mantle but wider syphon opening. Gaping clams do not fully extended the mantle.

OrionN · Mar 19, 2024

Examples of gaping from the internet

TViquez · Mar 19, 2024

OrionN said:
That clam looks very healthy to me. No problem I can see. gaping of the clams would show retraction of the mantle but wider syphon opening. Gaping clams do not fully extended the mantle.

Good to know! That makes sense that the mantle would retract as well as gaping if it was having issues. Thank you for putting my clam newbie mind at ease!

TViquez · Mar 19, 2024

OrionN said:
Examples of gaping from the internet

I see what you're saying about the mantle retracting as well. The width of mine isn't quite as wide as that one but pretty close. What exactly makes it open wider sometimes?