Black spots on Favia

[reeferpdx415]

Hello friends. I've been having some trouble with my corals lately and am concerned for one in particular. I have a medium to large Wolverine type favia colony. It had a small black spot on it when i got it but was told it was just algae. I'm no starting to see more of them and I'm worried is starting to recede a bit. Also, a similar black spot on a couple of Acan. Any idea what it is? Here's a couple of pics.

FAVIA

ACANS

 

[Mr. Mojo Rising]

Would you please turn off the blue lights and leave only the white lights? Its hard to see like this.

 

[reeferpdx415]

Would you please turn off the blue lights and leave only the white lights? Its hard to see like this.

FAVIA

ACANS

 

[Sophie"s mom]

I feel certain it is algae as I also have a favia that developed an area like this when I had it in a space with not enough light. I moved it to better light and it has not gotten any worse, maybe even a bit better.

 

[BristleWormHater]

Looks like your having some algae problems. For favia I'd do 150ml of 3% Hydrogen peroxide in 1 liter(4 cups) of tank water, dip for five minutes. The coral will suffer a bit from the dip, but should bounce back within a week.