Brown spots on bubble coral

[Jarret]

Not sure how well you can see in the picture but this bubble coral at the LFS I work at has brown spots developing on it. I can't tell if they are on the inside or the outside of the coral.

The water parameters in our tanks aren't that great unfortunately so I'm sure that is the cause of the issue. My question is can anybody tell me what this might be?

It almost looks like algae/diatoms.

 

[skh]

I can't tell from the picture but one common affliction for bubble coral that looks like brown spots is red/brown planaria flatworms.

 

[Jarret]

Definitely not flatworms, this stuff isn't as uniform and its in patches.