Odd Thing in Tank

[RandomPersonGuy]

I've had a freshwater tank for many, many years, but about a week ago I noticed an odd white, fuzzy mold-like thing in my tank. I have a large rectangular piece of black marble in my tank, standing straight up. This mold-like thing appeared there, on the marble, only recently, and is usually situated in a fan-like position.

Normally I wouldn't think much of it, but the odd thing, is, it seems to be alive. If you just sit and stare at it, it doesn't appear to move at all, but every morning when I check it out again, it has moved to a different location on the slab of marble. It also leaves an odd, vein-like trail wherever it moves. One morning it would be at the bottom of the marble, the next it would be at the top, and the day after it would have started moving to the opposite side.

While I've never actually seen it move myself, it very clearly ends up in different locations every day. Does anyone know what this could be? I have no means to take a photo, and I know I'm not very good at describing things, but that's the best I can do, unfortunately.

I'm really curious since I have no idea what it is, where it came from, or even if it's dangerous. All of my fish seem fine, and I clean the tank regularly, so I don't have a clue.

 

[ArtistGardener]

Maybe a hydra? Have you added plants or anything else from another tank recently?

 

[RandomPersonGuy]

I haven't put anything from another tank into my tank recently, no. I have replaced a few of my old plastic plants with new ones a couple months ago but that's the only change I've made recently. I assume that picture is magnified? It obviously looks nothing like that to the naked eye. To the naked eye it just looks like a bunch of white mold or something along those lines.

 

[jlk]

Fascinating life form you have in your tank! Its actually a slime mold and they are extremely rare in aquariums. Very little is known about them in terrestrial environments and even less is known about those that show up once in a blue moon in aquatic habitats. It is collectively 'alive' and it does move (its eating the algae/film growing on surfaces) but it is also harmless. And apparently very difficult to eradicate fully. I am going to try and post two links, however, I can not guarantee they are still good as they are from a few years ago. I believe the first link had decent pictures if you scroll down to the middle of the page.

http://waynesword.palomar.edu/slime1.htm

An extraordinary life form in aquariums - Freshwater Aquatics - JBL


edit: hopefully, the top link now works!

 

[RandomPersonGuy]

Ah, that looks like just the thing. Thank you very much. I'm glad to know that it's harmless. Since it doesn't sound like it causes any trouble in the tank, and the fact that it sounds so rare, I see no reason to try and get rid of it, in that case.

I still have no idea how it even appeared in my tank, but I guess that information isn't as important as knowing what it actually was. Again, thank you very much. That's a load off my mind.

 

[jim532]

If it were in my tank, I'd want to at least try to remove it before it became a nuisance.
I'd be afraid it would start spreading all over and start to look unsightly. My plan of action would be to start with some extra water changes and gravel vacuuming for a while. Then give all my rocks and decorations a bleach dip and 3 minute bath in boiling water. Finish it off with some decorative Nerites to hopefully eat whatever is left.


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[Fishobsessed7]

I'd keep it since it so rare


Fishobsessed7

 

[NigelK8485]

Would that not be a sign that something is off in your tank if it's there to eat dead and decaying materials? While it's kind of cool because it's supposedly rare, it just doesn't seem like a rarity you'd want to have...a mold or fungus.


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[jlk]

Would that not be a sign that something is off in your tank if it's there to eat dead and decaying materials? While it's kind of cool because it's supposedly rare, it just doesn't seem like a rarity you'd want to have...a mold or fungus.


Sent from my iPad using Aquarium Advice

Please read the links posted above. It's not a mold or a fungus but a completely different branch on the tree of evolution. It is a harmless, living 'thing' and it likely is much more proficient than any snail or tank 'cleaning' creature out there.

I find these oddities quite amazing but I would love to know where they come from/how they could possibly wind up in someone's tank. Quite a mystery!


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[Fishobsessed7]

Please read the links posted above. It's not a mold or a fungus but a completely different branch on the tree of evolution. It is a harmless, living 'thing' and it likely is much more proficient than any snail or tank 'cleaning' creature out there.

I find these oddities quite amazing but I would love to know where they come from/how they could possibly wind up in someone's tank. Quite a mystery!


Sent from my iPhone using Aquarium Advice

I agree. They are quite neat and interesting!


Fishobsessed7

 

[NigelK8485]

Please read the links posted above. It's not a mold or a fungus but a completely different branch on the tree of evolution. It is a harmless, living 'thing' and it likely is much more proficient than any snail or tank 'cleaning' creature out there.

I find these oddities quite amazing but I would love to know where they come from/how they could possibly wind up in someone's tank. Quite a mystery!


Sent from my iPhone using Aquarium Advice

I read them. I meant to say something that looks like a mold or fungus. To each their own, for me I just wouldn't like it for aesthetic reasons. But, at least for me, when I've had snails in my tank I would have to add food to the tank to ensure they got something to eat. If this slime mold is just growing on its own without any additional nutrients being added, wouldn't that signify maybe over feeding or a surplus of decaying material that is being able to fuel the growth?


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[jlk]

I read them. I meant to say something that looks like a mold or fungus. To each their own, for me I just wouldn't like it for aesthetic reasons. But, at least for me, when I've had snails in my tank I would have to add food to the tank to ensure they got something to eat. If this slime mold is just growing on its own without any additional nutrients being added, wouldn't that signify maybe over feeding or a surplus of decaying material that is being able to fuel the growth?


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I actually think it indicates a healthy, thriving aquatic environment that is very well established and mature. Aquariums are not sterile nor 'clean' environments. Mature tanks have a variety of biodiversity in the species of organisms that inhabit them. Most are not visible to the naked eye or are only apparent in abundance. And they exist in a constant flux of life, death and decomposition. This creature is simply playing its role in the cycle of life in this particular aquarium.