Anyone know what this is?

[Cleo21]

Looking to figure out what this is and how to get rid of it. Found it in my pleco tank. Thanks so much.

[bekateen]

I have no idea. Looks like a fungus, but that's just a guess.

Cheers, Eric

[Fallen_Leaves16]

It is a form of freshwater sponge, or so I am told; indicative of good water upkeep and whatnot, not really detrimental in any way.
I could be wrong, though; might be best to wait for others to chime in.

[OregonOutdoorsChris]

I will second freshwater sponge. Probably from the genus Ephydatia.

I have some as well, and the only problem I have is it's in a planted tank and it kills plants it covers, it spreads by spores if you move anything from an infected tank to another, and I have yet to discover a way to kill it other than manual removal (but spores remain and it comes back).

[Fallen_Leaves16]

I will second freshwater sponge. Probably from the genus Ephydatia.

I have some as well, and the only problem I have is it's in a planted tank and it kills plants it covers, it spreads by spores if you move anything from an infected tank to another, and I have yet to discover a way to kill it other than manual removal (but spores remain and it comes back).

Do plecos seem to eat it at all? I know there are a good number of species (Parancistrus spp. for instance) that consume freshwater sponges; likely a completely different sort of sponge, but those white flat blob things are still sponges...
Odd that it seems so invasive. The few people I know that had them found that they were slow growers and typically only grew on rock, wood, or glass; perhaps some species are far less particular and sensitive than others.

[OregonOutdoorsChris]

I don't have any plecos, so I could only guess. If there were a commonly available pleco species that is easy to care for and eats this sponge, I would certainly be interested in hearing about it .

But from my experience so far, I can tell you otos, cherry shrimp, and amano shrimp don't eat it.

[Kirin]

I will second freshwater sponge. Probably from the genus Ephydatia.

I have some as well, and the only problem I have is it's in a planted tank and it kills plants it covers, it spreads by spores if you move anything from an infected tank to another, and I have yet to discover a way to kill it other than manual removal (but spores remain and it comes back).

Do plecos seem to eat it at all? I know there are a good number of species (Parancistrus spp. for instance) that consume freshwater sponges; likely a completely different sort of sponge, but those white flat blob things are still sponges...
Odd that it seems so invasive. The few people I know that had them found that they were slow growers and typically only grew on rock, wood, or glass; perhaps some species are far less particular and sensitive than others.

Quite a few genera are reported to, I believe Megalancistrus as well, maybe Pseudacanthicus as while carnivores they do have some very robust teeth/jaws with more numerous teeth then normal for a carnivore. I'm not 100% they are digesting or actually eating the sponges opposed to extracting other organisms on and around the sponges. No doubt they probably wont feed on all sponges, there are images of those found in Loricariid habitats.
I believe quite a lot of the sponges want suspended sediment long term, there are also bryozoans which similarly filter feed and do occur in aquariums. This is also a sponge in my opinion, but no idea what sponge, there are so many freshwater sponge species.