OT: White wavy threads on glass, plastic, and wood

[astrid37]

Hi All, Happy to be here! I've been dealing with these numerous white wavy things on my glass of my cory tank (photo below), driftwood, and the bubble disk for the last two months, since I started the tank. I have tried wiping down the sides and done all of the requisite water changes, to no avail. At first I thought it was columnaris but I think all of my fish would be infected by now if that were the case? I don't think that I am overfeeding the tank. I'm mystified. Anyone have any ideas about what it is, how to get rid of it, and is it dangerous to the fish? Thanks so much!

[dw1305]

Hi all,
By zooming in on the lower photo I think they might be Hydra.

Do they look like this in close up? and



Do you feed your fish a lot of small live food items? (Daphnia, BBS, Grindal worms, Micro worms etc)?

cheers Darrel

[bekateen]

Yeah, really not much detail to go on, but I agree with Darrel that the most likely answer is Hydra.

Cheers, Eric

[Bas Pels]

I once had green Hydra. At least, I assumed them to be Hydra. Therefore, if het color doesn't match, I wouldn't pay attention to that

[dw1305]

Hi all,

I once had green Hydra. At least, I assumed them to be Hydra. Therefore, if het color doesn't match, I wouldn't pay attention to that

That is Hydra viridissima, it has a symbiotic algae (a Chlorella spp.) in its tissue (just like the zooxanthellae of corals).

I get both green and clear ones in the tanks. I've never looked in detail but I assume that the the clear one is Hydra oligactis
(http://www.lifeinfreshwater.org.uk/spec ... 2.jpg.html), which is common in the UK.

cheers Darrel