What in the **** is this in my tank!

  • We are currently upgrading MFK. thanks! -neo
That looks like a hydra which are not harmful to fish that I know of.
 
Hydra. Not a bad thing, just ugly, believe me I've seen way worse "things" in some if my tanks before such as transparent mushroom like things that almost killed one of my fish.
 
Just think of them as anenomes :)
 
hydras, I think, are awesome haha. I have them in a 55 with my pickerel and sunfish. There will be occasions that I may feed one of the larger ones with a blood worm or two haha, interesting to watch for sure.
 
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