Base of SPS bleaching

[nevets9333]

Hello!

 My tank has been running for a couple years now, over the last 8 months I starting trying a few SPS corals. They have grown a decent amount and still look like they are growing, but the bases are bleaching out. Is this just due to shading or part of a bigger problem? From the top they still look healthy. All of my parameters are still in line-

Alk: 9.5

CA: 440

MG: 1300

Phosphate: 0

Nitrate: 2

 

Not sure how useful this first picture is. I can try to get a better one. It is definitely losing color at the bottom of the coral. 

 

Thanks in advance! 

[Clown79]

It is common for the underside of the coral to do this when it grows large enough to not allow light to the lower portions.

 

Another issue is lack of flow, that is another common cause for the receding flesh beginning at the base

[nevets9333]

Thank you for the response Clown79. I don't think it is the flow since I have an MP10 pretty much right next to it. Besides the aesthetics, is this detrimental in the long term? I plan on getting a new light and raising it up higher to hopefully increase the spread decrease the shadowing. 

 

Also, I saw somewhere that dosing iodine can help with this. Since I don't test for it I have hesitated to try..

[Clown79]

Dosing iodine is tricky. You need to test it or it can be over dosed easily. The tests kits aren't reliable.

 

As far as I know, as the coral grows, this occurs and is a natural occurance. Even adding a light may night help because it's the underside of the coral.