Well as to trying to get them to come out more, they are very shy species and they seem to have very good eyes sight and are very cautious of our presence. Try to reduce the light a bit and don't stick your head directly (too close) near the glass. It usually takes some time before they will come out to feed openly. Also, if you have a group of them, they tend to be not as scared! Good luck with your shrimps! And post more photos!