I keep them they are interesting to watch grow too approx 1.5 in will be fine in a 30L needs to be planted and with a well fitted lid as the jump out of aquariums very easily. They don't breed in freshwater so will not cross breed with other shrimp
cool, thanks Jo. The lid may be a problem as its a dennerle tank, just has a bit of glass with gaps round it, might be able to sort something out though.