Worm-looking things in my 2 gallon tank

[GayleA]

Hi - I have a 2 gallon planted tank, under-gravel filter with no fish. I had a few lamb-chop tetras that I removed to another tank about 3-4 weeks ago. Today, I added some tap water and saw these little worm-like things swimming in the water. There are really a lot of them but you can't really tell by the picture. Can anyone tell me what it is? I have the same plants in my 10 gallon with about 13 fish and I don't see these worms in that tank. I appreciate any help with this identification!

[Dawn T]

Looks and sounds like detritus worms.

[Colu]

Definitely detritus worms

[patricia]

most defiantly detritus worms dont add any fish or plants yet empty tank and do a lot of cleaning, rocks (sand), glass, deco, ect., refill add your water conditioner  and let the tank cycle when adding fish get cory's trio meds and Quarantine for a couple weeks (or follow instructions on quarantine meds)

[PotatoFish]

11 hours ago, GayleA said:

Hi - I have a 2 gallon planted tank, under-gravel filter with no fish. I had a few lamb-chop tetras that I removed to another tank about 3-4 weeks ago. Today, I added some tap water and saw these little worm-like things swimming in the water. There are really a lot of them but you can't really tell by the picture. Can anyone tell me what it is? I have the same plants in my 10 gallon with about 13 fish and I don't see these worms in that tank. I appreciate any help with this identification!

The detritus worms probably started getting bolder and more numerous because they don't have those tetras picking them off any longer. The fish in your other tank probably snap them up, unless they are so big that the worms are not worth the effort.

[Schwack]

I've had detritus worms in just about every tank I've setup. The first time I saw them, I freaked out (the same for most new fishkeepers, I'm sure.) All the resources I have suggest they aren't a problem, unless you really object to tiny worms floating about. My CPDs and rainbowfish seem to enjoy snapping them up when they move through the water column and everything I've found says they're entirely harmless to fish. I've also read that they have some beneficial impact as far as sifting through waste and uneaten food which falls into your substrate.

I'm no expert, but as far as I'm concerned, they're just a normal part of an aquatic ecosystem. Actively fighting their existence sounds like an uphill battle for minimal benefit.

Edited December 27, 2020 by Schwack

[FishyThoughts]

16 minutes ago, Schwack said:

I've had detritus worms in just about every tank I've setup. The first time I saw them, I freaked out (the same for most new fishkeepers, I'm sure.) All the resources I have suggest they aren't a problem, unless you really object to tiny worms floating about. My CPDs and rainbowfish seem to enjoy snapping them up when they move through the water column and everything I've found says they're entirely harmless to fish. I've also read that they have some beneficial impact as far as sifting through waste and uneaten food which falls into your substrate.

I'm no expert, but as far as I'm concerned, they're just a normal part of an aquatic ecosystem. Actively fighting their existence sounds like an uphill battle for minimal benefit.

Yeah, I came across the same first time I had seen them in my tank. And the only negative does seem to be just the sight of them when they venture out of the substrate. 
 

Would be interested to hear if anyone knows of some true cons to them though. 

[GayleA]

Thank you everyone for your comments. I'll water change today and consider adding some hungry fish to the tank.