what's this doing in my fish tank??????

[flowerfairy]

Found this in my fish tank today, possibly came in on some plants I bought 2 weeks ago.

Not a clue what it is - could it be some sort of larva? are there likely to be more? will they eat my fish if I don't catch them quickly enough?

sorry for the lack of clarity, my camera doesn't do close ups!

[Gill Catton]

looks like a hog louse totally harmless for your fish. Is it a coldwater tank? Probably won't survive for long at the temperature fluctuations in a tank are often too much for this type of animal.

[The Woodman]

I agree with Gill, it's a Hog Louse - Asellus aquaticus

Good image here
Google Image Result for http://www.naturephoto-cz.eu/pic/krasensky/asellus-aquaticus-1494.jpg

It won't eat your fish, they are more likely to eat it.

However, I would remove it unless you have a "natural" tank as they may vector infection and parasites.

[flowerfairy]

Thank you, that's reassuring!

My baby catfish got eaten by a goldfish, so this wasn't the culprit!

My tank is usually at about 21.5 degrees, surely the fluctuations in temperature in a stream will be more than in a fish tank?

I think I might put it back in if they can live together ok, as I don't know what else to do with it - it's currently in my washing up bowl with a couple of scuds(?) that I found on the filter.

It looked happy trolling around the bottom of my tank, happier than in my washing up bowl anyway!

[Gill Catton]

Originally Posted by flowerfairy

Thank you, that's reassuring!

My baby catfish got eaten by a goldfish, so this wasn't the culprit!

My tank is usually at about 21.5 degrees, surely the fluctuations in temperature in a stream will be more than in a fish tank?

I think I might put it back in if they can live together ok, as I don't know what else to do with it - it's currently in my washing up bowl with a couple of scuds(?) that I found on the filter.

It looked happy trolling around the bottom of my tank, happier than in my washing up bowl anyway!

As a general rule, the smaller the boy of water the greater the fluctuation in temperature (the quicker it heats up and cools down). I had tropical fish for a while and if there was a particularly warm summers day this often would kill off my algae shrimps in the tank before I had a chance to do anything about it.

[flowerfairy]

My tank is 100 litres, but unfortunately when I moved here I hadn't seen the house before, and arrived in the evening. I didn't realise that where I set the tank up the morning sun shines right on it, so I have to leave my kitchen curtains closed all morning to stop it heating up, otherwise I will have to catch about 50 fish (mostly catfish babies) drain the whole thing, find 2 strong men to move it and rearrange my room (hmm, not much chance of that at the moment!)

[Gill Catton]

Yeah mine was 180 litres and not even in direct sun! But then it was a tropical set up so warm to start with.