Dark Brown/black encrusting algae?

[Mathnes]

I have this dark brown/black algae? On my rocks. I’m pretty sure it came in my system from a fragpl plug. It is encrusting and doesn’t come off easily when scraping. It does feel a bit soft to the touch but it doesn’t seems to be a sponge as it is not plump or does have any holes or intake on it. It is present on almost every rock in my reef and want to know what I’m dealing with. Could anyone id this? Spreading fast! Thank you

 

[Tinnerito]

I have this dark brown/black algae? On my rocks. I’m pretty sure it came in my system from a fragpl plug. It is encrusting and doesn’t come off easily when scraping. It does feel a bit soft to the touch but it doesn’t seems to be a sponge as it is not plump or does have any holes or intake on it. It is present on almost every rock in my reef and want to know what I’m dealing with. Could anyone id this? Spreading fast! Thank y

Bump!

 

[Borat]

Not good.. let's wait for doomsday fellas to chip-in and diagnose, but that's really not looking good.

 

[skiergd011013]

I have similiar in my 3 month old reef that i started with dry rock, so i doubt its anything bad. Its a hard, encrusting substance, almost like brown coralline

 

[Mathnes]

I have similiar in my 3 month old reef that i started with dry rock, so i doubt its anything bad. Its a hard, encrusting substance, almost like brown coralline

I have some coralline on other areas and that is harder then this. I searched everywhere and similar posts never get answered. Hope someone know what it is.

 

[Mathnes]

I have some pieces off live rock aswell and it doesn’t seem to grow there. Only on my dry rock

 

[skiergd011013]

I have some pieces off live rock aswell and it doesn’t seem to grow there. Only on my dry rock

Mine only grows on the rock as well. My powerheads have purple coralline, and glass a little bit of coralline. Look up bracket brown seaweed/Lobophora. I think thats it. Maybe it feeds off of something in new, dry rock? I have some gulf live rock in isolation right now that i will add a few chunks soon to seed my dry rock. I havent had any algae issues in 3 months since i started this tank. This brown encrusting algae we both have doesnt look like an issue to me? Probably just one step in the maturing process of the dry rock.

 

[ZzyzxRiver]

I’m not sure what it is, but I had a good amount of something similar on dry rock and emerald crabs scraped it clean off.

 

[Mathnes]

the lobophora is plating as it seems, it doesn’t anywhere in my reef. Chicken liver sponge is another thing I consider. never had any algae problems aswell, my tank has been running for 8 months now. I hope it is nothing to worry about. But it is spreading fast and as I ordered a new tank and I like to now if I can take these rocks or need to toss them. https://www.reef2reef.com/threads/brown-spots-on-rock-in-new-tank.296120/

This is a similar post and there are many others that never seem to get answered.. just google ‘ brown/black spots on rock reef’ might be a good sign or not? Hope it is nothing to worry about. But would be nice if someone has a definitive answer

 

[Mathnes]

I’m not sure what it is, but I had a good amount of something similar on dry rock and emerald crabs scraped it clean off.

Thanks, will try that!

 

[KrisReef]

Bryozoan suspect..
So many possible encrusting community members and only The Lord might properly be acquainted with them?

 

[skiergd011013]

the lobophora is plating as it seems, it doesn’t anywhere in my reef. Chicken liver sponge is another thing I consider. never had any algae problems aswell, my tank has been running for 8 months now. I hope it is nothing to worry about. But it is spreading fast and as I ordered a new tank and I like to now if I can take these rocks or need to toss them. https://www.reef2reef.com/threads/brown-spots-on-rock-in-new-tank.296120/

This is a similar post and there are many others that never seem to get answered.. just google ‘ brown/black spots on rock reef’ might be a good sign or not? Hope it is nothing to worry about. But would be nice if someone has a definitive answer

Mine neither, i havent seen it plating. Im going to try to not worry about it and assume its just cycling dry rock. Everything has been good and happy in my tank so far. Im excited to add some chunks of my gulf live rock. Hopefully it doesnt introduce some plague hitch hiker

 

[skiergd011013]

Here are some closeups of this algae/growth. I pulled out two chunks of my dry rock today and replaced it with gulf live rock. This dry rock has been in the tank for 3 months. I do not think it is lobophora (wafer algae). This stuff does not plate like lobophora. It seems to be strictly hard encrusting. It is not very slimy, like lobophora is known to be. It feels pretty much like rock when you touch it, with just a slight biofilm feel. I suspect it is either an aggressively growing brown coralline, or just some other natural cycling of the dry rock. I also have some brownish dots of coralline on my skimmers intake cover. I can also confirm that purple coralline is growing ontop of this stuff. I can easily find purple dots on it in various spots.

 

[Mathnes]

Here are some closeups of this algae/growth. I pulled out two chunks of my dry rock today and replaced it with gulf live rock. This dry rock has been in the tank for 3 months. I do not think it is lobophora (wafer algae). This stuff does not plate like lobophora. It seems to be strictly hard encrusting. It is not very slimy, like lobophora is known to be. It feels pretty much like rock when you touch it, with just a slight biofilm feel. I suspect it is either an aggressively growing brown coralline, or just some other natural cycling of the dry rock. I also have some brownish dots of coralline on my skimmers intake cover. I can also confirm that purple coralline is growing ontop of this stuff. I can easily find purple dots on it in various spots.

Thanks for getting back, mine seem to grow over the purple algae(see pic) and seems to be more brown as yours. The feel is the same as yours, not exactly as rough as rock but not very slimy as well. I noticed my Trochus snails eat it a bit. I’m going to try an urchin and maybe a emerald crab. I still have time to figure this out and if I can control it before my new tank arrives. Will give an update. Might ask my Lfs if they now what it is as I know exactly on which coral it entered my system and they definitely have it in their system or dealt with it.

 

[Mathnes]

Just an update regarding the dark /black brown algae as I switched tanks I didn’t take any of the rocks from the display with me. I also removed any frag plugs and scraped it of any coral skeleton it was on. Also a lot of my snails had it on there shell, so they are still in a bucket separately.
I took this as an opportunity to do some experimenting. I left a rock in the sun for a few hours. This didn’t seem to affect it in a noticeable way. I put my old rock in a citric acid solution this took at least a week to dissolve the algae. I still have a bucket with some affected rock together with the snails. I treated the snails(shells) and the rock for 3 times with peroxide and it seems to be slowely go away over a course of 2 weeks now. A week ago I also put a urchin in the bin with the snails and rock and it didn’t seemed to eat it aswell. Positive now that it isn’t a sponge but a coralline algae from hell. It completely took over all my rock when I broke down my tank and grew over my purple coraline algae. Hopefully I don’t get it in my new tank. And if I do I just better of throw anything that has a speck of it in the bin.

Last pic from my old reef with black rocks