Photosynthetic sponge melting?

[wmv]

Hey everyone, so I got this big rock covered in photosynthetic sponge a couple of weeks ago from someone local. It was doing great until a couple days ago I noticed a spot receding and exposing what looks like white fibers. Now this morning it appears to be spreading. does anyone know what causes this or how/if I should treat it?

 

[wmv]

This picture might help see the fibers better

 

[ISpeakForTheSeas]

I noticed a spot receding and exposing what looks like white fibers. Now this morning it appears to be spreading. does anyone know what causes this or how/if I should treat it?

Those seem to be places where algae has begun growing on the sponge - when they're optimally healthy, they should be producing chemicals that keep (at least most) algae from growing on them.

With a photosynthetic sponge, lighting are flow are key components of good health, so how is your PAR and flow in the tank for the sponge? Adjusting these as needed will likely help address the root cause (less than optimal health for the sponge).

For immediate remedies (which are recommended, though the root causes should be addressed if possible):

Yes, some sponges succumb to biofouling from algae and Cynobacteria. On the reef, herbivores keep sponges clean. In display tanks, I have noticed angels, tangs and lawnmower blennies grazing on sponge biomass and sponge regenerating tissue quickly. I sometimes use a toothbrush to deal with nuisance algae on sponges and remind myself to get more janitors: hermits, snails………

 

[wmv]

Those seem to be places where algae has begun growing on the sponge - when they're optimally healthy, they should be producing chemicals that keep (at least most) algae from growing on them.

With a photosynthetic sponge, lighting are flow are key components of good health, so how is your PAR and flow in the tank for the sponge? Adjusting these as needed will likely help address the root cause (less than optimal health for the sponge).

For immediate remedies (which are recommended, though the root causes should be addressed if possible):

That's kind of what I figured, which is why yesterday I actually turned up my lighting and wavemaker. It's under an AI Prime at roughly 100% whites and blues now with decent flow. There's not much algae on it but detritus had been settling on it a lot which I try to blow off with a turkey baster. Would detritus be causing this the same way algae would? Thanks for your help

 

[ISpeakForTheSeas]

Would detritus be causing this the same way algae would?

If enough detritus piles up, it could smother those parts of the sponge, so yes.

 

[wmv]

If enough detritus piles up, it could smother those parts of the sponge, so yes.

Definitely what I think the problem is then, which I think I have taken care of for the most part. Do you know If I should cut off the affected areas to prevent the spread? Or does that not make a difference as the areas will only die off if they're being covered?

 

[ISpeakForTheSeas]

Do you know If I should cut off the affected areas to prevent the spread? Or does that not make a difference as the areas will only die off if they're being covered?

I don't know that it matters, but some people remove them to be safe.

 

[Subsea]

Definitely what I think the problem is then, which I think I have taken care of for the most part. Do you know If I should cut off the affected areas to prevent the spread? Or does that not make a difference as the areas will only die off if they're being covered?

I have cut off sections of tree sponge to remove the uglies. Some regenerated and some continued to waste away.

 

[wmv]

I have cut off sections of tree sponge to remove the uglies. Some regenerated and some continued to waste away.

I was able to get in there with a scissor and cut off most of it, it's a huge colony so I'm hoping most of it survives