Maxima color change


New member
My nice little 2" blue maxima is going through a color change and I am wondering if this is normal or something I should be worried about? Tank size is a 20g high with 175w MH 10,000K. I feed DT's every other day, there is no skimming on this tank so there should be plenty of bacteria, plankton, etc...for the clam to feed on. I also have a small refugium in this tank. Tankmates are 1 firefish, 1 percula clown, and 1 scissortail goby (my other one jumped ship the other day:( ), 2 camelback shrimp (they do not bother the clam, I know, I've watched them!), turbo and astrea snails, 1 small brown atlantic cuke.

When I bought the clam, he was an overall rich blue with some electric blue striping down near the incurrent/siphon area. Also, right around the excurrent siphon it was bleached white. This was a very small area though. Now around the siphon it has turned gold, and the electric blue stripes have increased and are starting to "come up" towards the mantle part. I also notice some gold spots starting to form here and there along the mantle. It's strange because where the rich blue was, it will turn almost brown, like it's losing the zooallanthe (sp?), then the next day or two, the bright blue will have taken it's place. Or a gold spot. Does this mean it doesn't have enough lighting? I can rig it so I could add a 55w PC with a 50/50 bulb or I can add a 20w NO actinic if you think it needs it. But I can't do both as there is not enough room. Unfortunately there is no way for me to buy another MH right now, if that is what the animal needs. BTW, the clam is not gaping and it reacts very well to shadows.

I am hoping that this is a normal thing for a clam to do and not the start of the animal dying. I was kind of thinking of starting up a clam tank, but if this animal dies, then I'm not so sure........
And if you think it's dying, what else can I do?


New member thing I forgot to mention, I just put a new bulb (same wattage) in the fixture, could this be the clam starting to bleach? Or is it just exchanging different zoollanthe? The bulb has been in for about a week. Before that it (the clam) was under 55w PC 50/50 and 20w NO actinic.

Thanks Freckles for reminding me about the bulb!!!:D


Premium Member
How old was you metal halide when you changed it. I am in the thinking that the life of a metal halide is 8-12 months of "usable spectrum". Meaning that after 8 months the degredation of the spectrum would start falling more rapidly. I am in the habit of changing them on a 8 month period so the old bulb doesn't shift too much. When the new one is placed in the color variance isn't nearly as bad as a 12 month old bulb eliminating any possibility of stress due to an increase in overall intesity without proper reacclimation....

Simply: changing a bulb after it's "life" has expired isn't a great idea unless you acclimate you tank to the new bulbs which will burn brighter with the proper/correct spectrum

It's a possible issue...



New member
First I need to apologize for not being very clear about the lighting. I work nights, and when I'm tired, sometimes I don't think or express myself very well.
Okay, right before I bought the clam I bought a used MH with a bulb from a guy in the want ads. I do believe the bulb was very old when I bought it, but I have no way of knowing how old. I had the MH over the tank for about a week when I decided to order a new bulb. So I switched the lighting from the MH to the PC and NO. This was in place for about a week and a half. Then I got the new bulb and put the MH back.

The stripes that are showing up are a lighter blue than the original color, but it isn't white. Or at least not yet. And the goldish spots look like the same color on some of the photos I've seen recently here....only on the photos here, the gold on the maximas are more in a line, not spots. Look at Kedds post, the first picture, the maxima on the left, that gold line is the same color as what my clam has, only mine is just spots. Will the gold form a line eventually? Is this a good thing?

So it's quite possible that the clam is reacting to the more intense lighting? Will it recover from this? If the clam doesn't like the lighting, why hasn't it moved on it's own? Even though the clam has attached to the bottom of the tank, I know how to cut it free without harming it and I can move it. Should I?

Thanks Physh1 for helping me!!:D


New member
Well, I feel like an idiot now....

On one of the other threads, they had a link to Aquatic Reflections clams.....and as I was scrolling through it, the very last row, the one on the far right has the same color stripes and all. I think what I actually have is an ultra maxima, not a regular maxima! Don't know why the clam was not showing colors like that before, but it sure is looking like that now!

Sorry to bother anyone, but heck, I thought the poor thing had a disease or was starting to bleach! LOL!!

It's been a long week.......

name change!
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