Cherry Shrimp Died

[The sea monkeys Rock]

Hi,

Just completed my fishless cycle. Added some Cherry shrimp yesterday and one died today.

Tank conditions:
PH 7.7
KH 2
GH 6
Temp 21.5 C
NO2 0
Ammonia 0

The temp has dropped from 25 to 21 degrees in 24 hours and the PH is higher than they woudl like, would those two things be enough to cause the little fella to pass away?

Thanks

 

[The sea monkeys Rock]

The other Cherry shrimp is very quiet, he's just resting on the drift wood almost motionless. The two Armano shrimp, well I cant see them anywhere!! Seem to have disappeared completely and its only a small tank :-(