Pink and reddish-brown spots on maxea clam mantle

[A.m.P]

Hey, I'm still rather new to keeping clams and don't have the experience to really have a great feel for what might be going on day-to-day with the animals. I bought a supposed maxima-crocea hybrid about a month ago, at the time of purchase is was an off-opal color with a fair bit of pink and almost-white blues. 

Under my lighting it has always looked a fair bit different, though at times it does show off a bit of its' old opalescent streaks, I'm running an AI prime do deliver around 250 Par to the rock it is on (5 or so inches below the water line). It's on said rock (really it is in a shallow hole) because it jumped off the rubble-peice I had attached it to and then totally-latched itself into a hole in the rockscape overnight and refused to let me budge it (I chose to instead rearrange the rockwork so it was as high as possible in the tank, but it still can't quite open all the way).

 

With that out of the way I was hoping to get some advice, information, or opinions on the bands of brownish and pinkish coloration around the mantle. I've read that they're everything from normal, to acclimation which can take months, to LED hot spots, to localized bleaching or overgrowth of symbiotic organisms from too much/little light-nutrient-etc. At this point I figured I would just ask and see if someone with more experience might have an opinion. 

The tank is a 12g nano-atoll and has no nitrate or phosphates, is minimally stocked, and I do 5% water changes weekly- dose two-part - and keep the alk around 10.5. The second picture is the most-similar to the clams' appearance, to my eyes at least, in person.

 

Thank you for your time!

Oh and it can actually open a bit wider than in my pictures , I just can't seem to not spook it with the camera >_< 

[Tom@HaslettMI]

Looks normal to me. 

 

It is important to note that tridacna clams look quite different when looking from above vs the side. 

 

Tom

[A.m.P]

Ah yeah, we were able to view it from above in the store and thank you, appreciate it. Trying to gather as much info as possible.

[Tamberav]

I wouldn't worry about the color at this point... however no Nitrate or Po4 is troubling and that rock looks very clean/new. Clams are filter feeders and you can easily starve the small ones in too clean of a tank. If the clam doesn't continue to grow/have bright white bands of growth, then it is time to worry. 

[A.m.P]

So far so good, fair bit of visible new growth and great reaction time still, the rock and tank aren't ancient and I don't really have much in terms of stock so it's pretty much nothing but inverts that get fed powdered fish food pellets and blanched veggies a few times a week. I've had a few bouts of algae but it all gets eaten or burnt off within a week or two and then the rocks are clean again, I have some brown algae on the undersides of the rock and a little green coraline, but that's about it haha.

[A.m.P]

As an update, I reached out to some actual Tridacnid farmers and was given some more information. They felt the distributor likely misled the Local store owners when they ordered their stock as what I received is almost certainly a Tahitian Maxima. Unfortunately these animals are very poorly-handled and even-worse bred often resulting in larger specimens passing away within a year, however at the size I purchased mine it is possible that it will recover from being dry-shipped for 15+ hours  (which is why the shell is bleached-white without algae or other life on it) as it may have not been forced to immediately spawn via being tossed into shallow pools of radically-different water-chemistry (both because of inferior color quality and its' small size). Or at least that's the best explanation I have for the color of the clam which is getting brighter-pink every day and immediately-resembles any clear-shot of a Tahitian, hopefully it continues to grow and thrive in the tank.