Algae pellets, blood worms, and Mosura shrimp food are all excellent food options for these shrimp. The shrimp I breed and sell are primarily S+ grade, so I will focus on how to care for CRS of that grade. In order to maintain pure and stable water conditions it is highly recommended to use filtered water either through the use of a reverse osmosis kit, or by purchasing it directly. Since our primary goal in our aquarium is stability, it is good to use a buffering substrate that is designed to maintain the ideal water parameters. A zeolite based substrate is deal for this purpose, I have used Amazonia Aquasoil to great success and would highly recommend it for a stable and reliable tank. 10% Water changes should be performed weekly, and the substrate should be cleaned monthly.
Crystal Red Shrimp (or CRS) are intermediate to advanced in difficulty depending on the grade. Lower quality grades such as C and B are similar in difficulty to Red Cherry Shrimp, while higher grades such as S and SS require a great deal more care and attention. The reason for this is that in order to achieve brighter and more specific coloration the shrimp were repeatedly selectively bred with shrimp with similar color traits. This has lead to a weaker and more inbred genetic strain, which is more susceptible to poor water conditions.
CRS are very sociable and peaceful tank inhabitants they have in my experience exhibited more aggression especially at feeding time than their Red Cherry cousins, their scientific name is Caridina cantonensis. Female CRS tend to be larger, and will generally stay on the tank's substrate or decorations. When females are seeking a mate, they release a chemical that the males can detect through their antennae and will seek out. On some occasions the males can be seen swimming as a swarm throughout the tank. CRS are more comfortable in large colonies of shrimp with plenty of surfaces to crawl on. They have what is called a thigmotactic response, which means they will become stressed if they do not have surfaces to be crawling on and touching with their many arms. Decorations or plants are a necessary part of a healthy shrimp colony.