What is this growth?

[Jtbennett929]

Hi everyone,

I noticed this growth on my rock and the base of my corals over the past couple of weeks.

It's a 125 gal tank, started about 5 months ago but the livestock and rocks were transferred from my smaller tank that was running for 13 months.

As of 10/6/23
SG 1.026
pH 8.1
Alk @ 10dKH
Nitrates @ 0
Nitrites @ 0
Calcium @ 420 ppm
Phosphate @ 0.01
Ammonia @ 0

Without seeing the following pictures, my local fish shop thinks it may be a sponge.

Any thoughts on what it is and if I should be worried about it?

 

[ISpeakForTheSeas]

Yeah, that's a sponge.

It doesn't seem to be bothering the corals there, so it's not likely to hurt them chemically; that means that the main thing to watch out for is if it's invasive (which looks likely from what I can see). As long as it doesn't start to grow over and smother the corals or block them from getting light, it should be harmless (even if it grows around/through the base of the coral), and you should be able to just scrape it off to control its growth/get it out of the corals' ways so they can keep growing unimpeded.

 

[Tuan’s Reef]

They peel right off. Have at it.

 

[Rick's Reviews]

I had similar on my GSP and it took over to the point where my GSP was not opening, you should set up 3 X bowls outside of tank filled with aquarium water from you tank, remove frag/GSP and place in first bowl, use new toothbrush to scrub off as much 'white' as possible (GSP are very hardy so you won't hurt it), place in second bowl and using a turkey baster just baste it as hard as you can, then third rinse it off by twirling around and dipping, place back in aquriam. (Throw bowls of water away)
It may take a few of these 'cleanings' but always do it outside of your aquarium

 

[Jtbennett929]

Yeah, that's a sponge.

It doesn't seem to be bothering the corals there, so it's not likely to hurt them chemically; that means that the main thing to watch out for is if it's invasive (which looks likely from what I can see). As long as it doesn't start to grow over and smother the corals or block them from getting light, it should be harmless (even if it grows around/through the base of the coral), and you should be able to just scrape it off to control its growth/get it out of the corals' ways so they can keep growing unimpeded.

Do I need to worry about scraping it off while in the tank or will that make it spread like algae does? I find it on the majority of my rock

 

[Rick's Reviews]

Do I need to worry about scraping it off while in the tank or will that make it spread like algae does? I find it on the majority of my rock

Yes definitely, do it outside of tank, it will only cost you a quick top up of water in aquriam , honestly this is how to manage sponge

 

[ISpeakForTheSeas]

Do I need to worry about scraping it off while in the tank or will that make it spread like algae does? I find it on the majority of my rock

Depends on the sponge, but- generally speaking - it’s better to be safe than sorry, so scraping it outside the tank isn’t a bad idea). That said, if you don’t want to pull the rock out of the tank, then you can scrape it off and suction it out of the tank (such as by scraping it and suctioning it out simultaneously with a steel straw).

 

[Rick's Reviews]

Depends on the sponge, but- generally speaking - it’s better to be safe than sorry, so scraping it outside the tank isn’t a bad idea). That said, if you don’t want to pull the rock out of the tank, then you can scrape it off and suction it out of the tank (such as by scraping it and suctioning it out simultaneously with a steel straw).

Also as an added note, before a filter change, clean and scrub as necessary inside aquarium, clean filters after