Maybe wrong place but Red Cherry Shrimp Questions

Hi, I'm not sure if this is the right place but I am not really sure where else to put it, I know afew of you guys were talking about red cherry shrimp the other day, they seemed like a good idea to me so I decided I would set up a tank and get afew

I have had a tank set up for over a week, with plenty of stones and 2 moss balls for them to do whatever they do with, I received them in the post today (I bought them from ebay) and checked on the internet on how to put them in the tank, it said to get them out of the packaging, into a tub and add 5% of the tank water every 2 minutes, I did this and eventually emptied them into the tank - they seemed fine exploring and wizzing around, went to play football and just got back to find some of them laying on the side at the bottom of the tank (I think they may be dead) and some more sitting just below the water surface, they are still alive because I put my finger in to see if they would move, but they don't look to healthy!

I am not sure if this is normal behaviour, I was expecting the odd loss but I don't want to loose them all, does anyone have any experience or advice to offer?

I have a big 5ft tank with my axolotl in it, I could put them in there but the filter is bigger and might suck them in or stress them out.

My plan originally was to get afew cherry shrimp in a seperate tank, breed afew of them and then put some in with my axolotl to clean the tank up a bit, add a bit of variety and maybe the odd snack!

If anyone has any advice it would be great!

Do you know what your water parameters are? Do you use any chemicals at all in the shrimp tank?

I did a test for amonia before I put them in (yesterday afernoon) and it is fine, all I have in the water are two moss balls, some stones and a plastic plant

I had a look at the tapsafe stuff I used and it doesn't say anything about copper on it, I heard tha copper can easilly kill them

I think the problem may lie in the fact that the tank has been set up for only a week, shrimp are very sensitive and usually wont survive any kind of cycling process and need a fully mature tank. apart from that cherry shrimp are meant to be pretty hard to kill so its the only thing I can of if you say no copper is involved. Id say lack of algae for food (i would have thought they would nibble at the moss tho) or nitrate poisoning is most probably the problem!