Derasa Clam mantel discolored

[stuccoman]

Should I be concerned about the discoloration in my Derasa clam. Aquarium up and running for 2 years now. Added clam this June.

Temp 76
Sal 1.025
Alk 10
pH8.3
Mg. 1400
Ca 440
PO3 0
NH3 0
NO2 0
NO3 10
All tested with API except Mg, salifert

 

[blaxsun]

Do you have a "before" image?

 

[stuccoman]

Do you have a "before" image?

I do not.

 

[Butcher333]

I have a Derasa that has discoloration in its mantle. It’s been bothering me for a long time, but it is still alive. I think I decided it was Perkinsus.

 

[minus9]

What lights are you using and how long is your photo period? Hopefully your reading of PO4 isn’t zero? The good news is your growth looks pretty good.
Although T. deresa are sometimes found in slightly deeper water compared to other clams, doesn’t mean that they should be kept in lower light, nor considered a lower light clam. Also, clams have the ability to direct or redirect how light in utilized in their mantles.
The discoloration could be from the lack zooxanthellae in those areas or a less dense population of them and iridophores?

 

[stuccoman]

I have a Derasa that has discoloration in its mantle. It’s been bothering me for a long time, but it is still alive. I think I decided it was Perkinsus.

Thank You

What lights are you using and how long is your photo period? Hopefully your reading of PO4 isn’t zero? The good news is your growth looks pretty good.
Although T. deresa are sometimes found in slightly deeper water compared to other clams, doesn’t mean that they should be kept in lower light, nor considered a lower light clam. Also, clams have the ability to direct or redirect how light in utilized in their mantles.
The discoloration could be from the lack zooxanthellae in those areas or a less dense population of them and iridophores?

LED, Edge M, I use one of the preprogrammed, Great Barrier Reef, sunrise at 6, highest intensity 7-5, moonlight 5:30-11:30, off until 6am. I have a 55gl and the clam is on the sand on the bottom. It has almost doubled in size in 5-6 months. Looks great just has some lighter, whiteish areas on mantel. As f
Thank you for your info.

 

[stuccoman]

Thank You

LED, Edge M, I use one of the preprogrammed, Great Barrier Reef, sunrise at 6, highest intensity 7-5, moonlight 5:30-11:30, off until 6am. I have a 55gl and the clam is on the sand on the bottom. It has almost doubled in size in 5-6 months. Looks great just has some lighter, whiteish areas on mantel. As f
Thank you for your info.

As far as PO4 results with API test I have never had any measurable PO4, but my algae growth indicates otherwise.

 

[minus9]

As far as PO4 results with API test I have never had any measurable PO4, but my algae growth indicates otherwise.

Yeah, API is garbage for any kind accuracy. Invest in a couple Hanna checkers and you'll be good to go. I'm not familiar with that light, but if there are hot spots or if it's too low in par, then that can cause some issues. But, the growth alone is a good indication that it's getting enough light. Derasas are one of fastest growers, so get ready for a big clam in a very short period of time (relatively speaking).
Tridacna clams mantles can shift color due to light spectrum shifts or intensity. The zooxanthellae count will pretty much stay the same throughout its life, but the way it's distributed and the color shifts can change depending on the conditions (water parameters and lighting). Quality and quantity of light will play a role in how the mantle appears or shifts.
I'm not saying you have to switch lights, but in the future, switching to a better full spectrum light will benefit the clam and your corals. Plus, once you seem your clam under a more natural daylight spectrum, you'll ask yourself why you didn't switch earlier.