I use cuttlebone bits in my red cherry shrimp tanks. They breed (wink). Yes, raising hardness requires adding stuff to my water because it's very soft. If you don't add cuttlebone bits or crushed coral (I've done both), you add something else (shrug). Betty Goetz _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member