What are these creature in my tank?

  • We are currently upgrading MFK. thanks! -neo
Planarians glide smoothly; these guys do the stretch/retract thing, just like earthworms and relatives...like leeches...

If you can describe how they taste, we might be able to ID the exact species...
 
either leach or planarian, not sure but suspect the latter. Doesn't matter too much either, but that the leach is vaguely more predatory to small stuff. They're likely thriving on the leftovers from notoriously-messy pufferfish :)

Some/most fish will eat them. Think about loaches or cory school (albino?) to both eat the beasties & compete for food-bits to starve them out, as should your Macrobrachium(?) prawn & guppies & even the BNPs.
In your stock they're unlikely to be a problem, only aesthetic.

Unrelated: What puffer sp. is that? How is the shrimp surviving??? - impressive :)
 
Unrelated: What puffer sp. is that? How is the shrimp surviving??? - impressive :)
The puffers are "Tetraodon schoutedeni" aka Congo Spotted Puffers. I also bred them 2 years ago here is a video
, but did not know what to do with them they were 114 of them and i had no space or time to grow them and sell them so I gave them away for free to a local fish store. the shrimps are the freshwater shrimps with red claws, I bought 15 of them because i was going on summer holiday. i put all of them in the tank, so that when i am away, the puffers would hunt and eat them, so i was away for 12 days and when i came back only 5 left. the puffers killed and ate 10 of them. so, the puffers when they can get food from me, they wont bother risking injury from the shrimps, but when they have no option, they will get more aggressive and will attack shrimps and even bristlenose pleco was killed by one of them and was eaten. I have these puffers now for almost 5 years, they are three and each of them has a unique personality.
 
If not planarians then what is it?
If I was not being clear...I would bet serious folding money that those are leeches. Not necessarily a problem; only a small percentage of leeches are bloodsuckers. Most are just scavengers but I wouldn't even guess what type these are.

They're big enough that you would certainly notice one if it was latched onto a fish. I'd do a couple of midnight spot inspections just in case, but odds are you're okay. :)
 
Pretty sure planaria don't stretch and change shape the way those in the video are doing...
 
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