There is definitely some confusion in this thread. Some are referring to CBS and CRS (Caridina) which like the lower PH waters with low KH and GH. Some are referring to the Cardinal Sulawesi shrimp which like a higher PH/KH/GH, which are the correct shrimp
To add the the problem cantsay39 is not the OP and is referring to CBS/CRS and his tank parameters are not those of the OP. Its not the first time he/she has caused such confusion. Please wait for the OP to post his tank parameters.
Cardinals are notorious for having low survival rates. Check out Xenxes 20L thread
, and DK's thread (refer to mermaid shrimp)
Nice blog BTW OP.