i just got a free mantis shirmp from a fisherman theat caught it off a drager off of ny but i dont know what kind it is so i will try to get a picture but any way i have had the shirmp which is like 5 inches in a 5 gallon tank for about a day and a half it has about a 6 inch layer of mixed crush coral and sand and perfect water but the shirmp just stays out in the middle of the tank it dose not hid or tunnel under the rocks it just sits their is this normal when you first get the shirmp or is their something wrong with it