Use RO water in your tank. NEVER USE hit sprays and all out as they stay in air and pollutes your tank water ending up killing your shrimps. In the pic it is exoskeleton left after molting. You can feed them zucchini, carrot, spinach, cucumber, sweet potato but all boiled (cut theae into wedges, boiled fir 10 mins and freeze) other that this feed them algae waffers or tetra bits. And leave them as it is..
