Yellow sludge

[Alan_Nunez16]

I need help from anyone who can ID this this, it’s on the rock, kinda of a yellow mustard color. It just appeared out of nowhere, it’s in a hidden spot so in could have missed it a couple of times. My tank parameters aren’t the best, well i should say, my nitrates are high and the other parameters are normal, I don’t know if this information helps

 

[praba775]

Hi I have some on one of my rock. My water parameters arent the best too. Like phosphate is literaly 1 ppm. But anyways, I usually siphone it up thinking it was detritus until I got a pair of hermit crabs who started to eat it all up. Right now I have a lot of that on my sand but no more on my rocks.

 

[twentyleagues]

Hard to tell for sure but appears to be a sponge of some sort.

 

[Hockeypunk1]

Probably a sponge

 

[Gumbies R Us]

A sponge

 

[Alan_Nunez16]

A sponge

Is it bad or good? I’ve never heard of sponges in a reef tank

 

[Nate Chalk]

Is it bad or good? I’ve never heard of sponges in a reef tank

Then you probably haven't been reefing long

Should be ok. Some are aggressive encrusting, release toxins etc

 

[praba775]

A sponge

A sponge huh, you see I have been reefing for only a few months now but I know quite a lot as I learned everything the hard way. That means I have witnessed many casualities. I have many pineapple sponges. But I dont know what sponge this is.

 

[praba775]

Sponge id please?

 

[twentyleagues]

Sponge id please?

@ISpeakForTheSeas may know. Might need a better pic though. I call it yellow.

 

[ISpeakForTheSeas]

Sponge id please?

@ISpeakForTheSeas may know. Might need a better pic though. I call it yellow.

Unless the sponge has a highly distinctive feature (like the pineapple shape of a pineapple sponge, for example), then your best bets for an ID are pics of the full sponge that are clear enough to show the texture and color, with either microscope pics of the spicules and spongin, or DNA testing.

This sponge doesn't look terribly distinctive to me, so I'm going to agree with just calling it a yellow encrusting sponge for now. Given the location, it may or may not be a cryptic sponge.

Regardless, it's most likely harmless/beneficial.

A couple of relevant quotes:

here’s a good Sponge ID resource for anyone who’s interested- as mentioned, though, sometimes DNA is the best indicator for telling sponges apart:
https://www.fao.org/3/i7773e/i7773e.pdf And, here’s a decent example of why sponge ID by non-microscopic sight is not always reliable:
https://www.researchgate.net/figure...rating-variations-in-shape-and_fig6_248716402

Yeah, that's definitely a sponge. Most sponges are completely harmless/beneficial, but some can be invasive and/or harmful to corals (thankfully, these are rare).

To tell if a sponge is chemically harmful: if a healthy, established coral starts closing up or looking to be in bad shape on the side closest to the sponge as the sponge grows closer to it, and nothing else has happened (lighting changes, parameter swings, pests, etc.) that could explain it, then the sponge is probably chemically harmful.

Chemically harmful sponges are very rare.

For invasive sponges: unless it shows signs of being chemically harmful or starts actively growing over and smothering a coral's flesh/polyps, it's harmless. These can grow over the skeletons of corals, around the base/stalks of corals, even up into the water column above corals (where they're over the coral but not growing on the flesh or polyps themselves), etc. without harming the coral at all - as long as the coral flesh and polyps can get food, light, and flow, the sponge is harmless.

Invasive sponges are moderately rare.

Invasive and chemically harmful sponges are incredibly rare.

 

[twentyleagues]

Lets just name it Sponge Bob hes yellow! I find him kind of invasive though.

 

[praba775]

No, not a cryptic nor a yellow encrusting sponge.

 

[praba775]

I tried to get a better pic of the " yellow sludge".

 

[twentyleagues]

I tried to get a better pic of the " yellow sludge".

I see what looks like a little detritus. Are you doing water changes and vacuuming the sand bed? That could be something like I had a couple months ago in a couple small places probably a cyano like algae. I just sucked it out during a water change. It came back a little less a week or so later, rinse and repeat. After 3-4 sessions it is gone. Wasnt exactly yellow or green but somewhere in between. Acted kinda like cyano with how it grew and sticking to the sand just wasnt red or the deep blue green I have seen in the past. In my tank it was popping up in areas of lower flow like just behind a rock blocking the flow or in a hole in a rock that would also be protected from flow.

 

[praba775]

I used to suck them up thinking they are detritus but I have stopped because I had an ich problem and I dont want it to come back just because I stirred up the sand too much.

 

[praba775]

Will a sand sifting starfish clean it up?

 

[ISpeakForTheSeas]

Will a sand sifting starfish clean it up?

Possibly, but starfish are known for starving in our tanks, so I can't recommend getting one. Suctioning it out and adjusting the rock/flow to make sure that's not a low/no flow zone would likely be a better approach.

 

[exnisstech]

Is it bad or good? I’ve never heard of sponges in a reef tank

 

[praba775]

Thanks