Cant fight algae in dt

[SantaMonica]

Looks like it's clustered in one area, so maybe P coming out of the rock there. Would explain other algae going away, and this one growing.

[Floyd R Turbo]

I don't think that's his tank, that's a stock photo

[kotlec]

I don't think that's his tank, that's a stock photo

Youp

[kotlec]

I of course am very happy that nobody has (had) this bad pest in their tanks.
Alone in the battlefield (not so happy).

[C-Horse]

You are not alone. On reef central there is thread devoted to getting rid of this algae.

One process involves wrapping the affected rock with plastic sheet and then injecting a small amount of 3% hydrogen peroxide into the
wrapped rock. Turn off all circulation pumps when doing this. The plastic sheet is to concentrate the peroxide on the algae.

You can also just remove the rocks and put in it a tank with some peroxide added to the water.

I of course am very happy that nobody has (had) this bad pest in their tanks.
Alone in the battlefield (not so happy).

[kotlec]

But there are some corals on the rocks. How much peroxide they will stand ?

[C-Horse]

Here is the link on reef central for you to read for more detail.

Another thing to try. Take the affected rock out and add a few drops on the algae, and rinse it with salt water then return to tank.

If you have a lysmata cleaner shrimp this is the only recommended method. The original poster said
"just enough drops to saturate the algae. if its a small tuft use one or two drops. let sit on the target for 2 to 3 mins (when treating I regularly leave my pico with 15 genera of mixed stony and soft corals emersed for 5 or more 2 to 3 is a safe zone)"

Link

But there are some corals on the rocks. How much peroxide they will stand ?