What is this? some sort of sea mold?

[Mike.B]

Alright so my old tanks just sitten with live rock in it with an xp2 running for circulation, minimal I know, but theres no fish and I dont care. I'm setting up my new 70g and Im wondering what the hell is growing in this 55.

Here are some pics





Im just curious, not really concerned but I want to know what this is?

 

[Chordstriker]

Looks like a spnoge to me. The guy at my LFS was pointing some stuff out that was growing in his display tank today that looked just like that. He didn't know for sure either, but thought it was a type of sponge.

 

[sage1970]

Tagging along here....

My GSP have got something like that growing on the area they are on.....

So, bumped with interest!

 

[reefD]

could be a sponge but also looks like die off. pick some out and sniff it. if it smells foul its die off. could be a sponge as the ussually look like that when the die.
if it is die off you could help keep it from continueing/spreading to corals by added flow.

 

[sage1970]

When I picked some of mine off...it kinda had a feel like rubber and no smell????

 

[mille239]

possibly a blue-green algae? like cyanobacteria?

 

[Mike.B]

Well Its not anything that was living in the tank, I had no sponges or anything like that, theres 3 patches of it all different places, that was the biggest.

Picked some up with a fishnet and it smells like a septic tank.

So it definetly something rotting, but what the only coral in the tank is some brown buttons and there alive. Is something dieing in the sand, really weird.

 

[wrott]

It's probably a bacterial mat--due to low flow. They are in the ocean as well.

 

[Mike.B]

interesting...so a very good indicator that a tank has low flow

My new tank wont have that