Oh crikey- I hope they don't hatch eggs! We have bloody millions of the things! They eat privit and blackberry leaves, brambles. They're really quite easy, but do seem to produce an unusually large ammount of...mess...for such small things. You need to clean them out. Our dd lines their tank with kitchen towel. And beware if they're the sort which flip around because we've had some dramas with springing out stick insects! Some aren't like that though, they just sit on sticks
They are a nightmare. I bought some for my children about 6 years ago. Bought 4, in 2 weeks had 24! I went on holiday for 2 weeks, took them into work for my friend to look after, came back and had about 224 (I may be imagining the numbers). One we named tripod because my friend had no privit to feed them and they started eating one of the older ones and he lost a leg! In the end, the tank was full of them, more insects than privit and I let them go in my neighbour's privit hedge (harsh I know). The hedge went a bit bald but then I think the cold weather killed them off. Sorry!