What’s covering my coral?

Aquanic · Jan 30, 2023

I did a water change and when I woke up this morning one of my corals had a white film over part of it. I dipped it in coral rx and it seems to be doing better. The film blew off in the dip but the part of the coral that was under it didn’t look good. Any help identifying what’s going on would be appreciated, thanks.

vetteguy53081 · Jan 30, 2023

Aquanic said:
I did a water change and when I woke up this morning one of my corals had a white film over part of it. I dipped it in coral rx and it seems to be doing better. The film blew off in the dip but the part of the coral that was under it didn’t look good. Any help identifying what’s going on would be appreciated, thanks.

Its a nuisance algae known as derbesia. The first thing you want to do is reduce your white light intensity and even the number of hours your white light is on.
This is one of the more challenging of algae due to need of its complete removal. Removal is best accomplished by taking the rock out of tank and placing in a container of tank water. Then you will want to pull as much as you can by hand and discard. With a dental pick or small crochet needle, pull the roots off the rock. YOU MUST GET EVERY ROOT OR IT WILL SIMPLY RETURN @!!3
After you are done return rock to tank and add the following cleaners which will help with control. These guys will consume this but not as fast as this algae can grow - They will never keep up.
Pin cushion urchin, Chiton snails, pitho crabs, and larger astrea snails

This procedure is not as bad or time consuming as it seems. Assure phosphate levels do not become elevated which helps feed this algae

Aquanic · Jan 30, 2023

vetteguy53081 said:
Its a nuisance algae known as derbesia. The first thing you want to do is reduce your white light intensity and even the number of hours your white light is on.
This is one of the more challenging of algae due to need of its complete removal. Removal is best accomplished by taking the rock out of tank and placing in a container of tank water. Then you will want to pull as much as you can by hand and discard. With a dental pick or small crochet needle, pull the roots off the rock. YOU MUST GET EVERY ROOT OR IT WILL SIMPLY RETURN @!!3
After you are done return rock to tank and add the following cleaners which will help with control. These guys will consume this but not as fast as this algae can grow - They will never keep up.
Pin cushion urchin, Chiton snails, pitho crabs, and larger astrea snails

This procedure is not as bad or time consuming as it seems. Assure phosphate levels do not become elevated which helps feed this algae

Thanks for the info. I’ll be sure to do some of that stuff to help get rid of the gha. I’m more concerned about the white stuff covering the coral, Ik the gha is a problem rn and I’ve been working on it to get it under control but it’s a bit of a process, as you pointed out.

I’d really like to know if this is a disease and if so what kind, ie bacterial, fungal, viral, so I can treat it. It doesn’t seem to be contagious as of now. The head that was under the white film looks like it’s melting and it turned brownish but nothing is coming off of it.

vetteguy53081 · Jan 30, 2023

Aquanic said:
Thanks for the info. I’ll be sure to do some of that stuff to help get rid of the gha. I’m more concerned about the white stuff covering the coral, Ik the gha is a problem rn and I’ve been working on it to get it under control but it’s a bit of a process, as you pointed out.

I’d really like to know if this is a disease and if so what kind, ie bacterial, fungal, viral, so I can treat it. It doesn’t seem to be contagious as of now. The head that was under the white film looks like it’s melting and it turned brownish but nothing is coming off of it.

Now I see it. Looks like what is known as Crysophytes and along with algae can be scrubbed off with a firm toothbrush or automotive detail brush and even some 3% peroxide and then return to the tank. Ninja star snails will keep this stuff controlled.
Is your tank at or near a window?

Aquanic · Jan 30, 2023

vetteguy53081 said:
Now I see it. Looks like what is known as Crysophytes and along with algae can be scrubbed off with a firm toothbrush or automotive detail brush and even some 3% peroxide and then return to the tank. Ninja star snails will keep this stuff controlled.
Is your tank at or near a window?

So it’s a type of algae? Why’d it grow only directly on the flesh of that coral? The tank is in the furthest corner from the window (15-20ft) and there’s a blackout curtain over the window that’s occasionally cracked when a dog looks out the window. Ironically the tank I have next to the window exploded in Dino then copepods bred into an absolute army and now it’s doin great.

vetteguy53081 · Jan 30, 2023

Aquanic said:
So it’s a type of algae? Why’d it grow only directly on the flesh of that coral? The tank is in the furthest corner from the window (15-20ft) and there’s a blackout curtain over the window that’s occasionally cracked when a dog looks out the window. Ironically the tank I have next to the window exploded in Dino then copepods bred into an absolute army and now it’s doin great.

Often its fueled by UV why I suspected nearby window.