Shrimp Temperature

[three-fingers]

I'm looking for something other than snails that i can put in my triops tank. Trouble is, that tank can go down to around 18 degrees Celsius during the night. Does anyone know if theres any shrimp that can tolerate this temperature? The tank the shrimp would be in is around 3 gals and will probably only be up for 2-3 months untill i need to dry it out and start over with the triops. In the meantime i could set up another similar sized tank or put them in my tropical tank. The easiest shrimp to get hold of here is cardina japonica.

Anyone any suggestions?

edit:The tank is just over 3.5 uk gallons.

 

[three-fingers]

OK well I've just asked my mum to buy some while she's out at the garden centre if she has time, since they are big ones there for around £3.80 each( ). Some websites say they can be kept at anything over 60 fahrenheit some say 23 Celsius. My tank is 20 during the night and 22 during the day, if anyone has any serious objections to why i shouldn't put them in there, please speak now.

EDIT:Well, they are purchased now, so we'll just have to see how it goes, i hope its ok for them...

edit again: They are fine just under 24 hours later, so anyone reading this who is wondering if these low temperatures are ok for amano shrimp...they are!