I have read that cuttlebone will increase the hardness of your water. I have really soft water from my tap, and have had difficulty keeping ghost shrimp alive - once they molt - they die. So, today, I purchased cuttle bones from the bird section at Petco in an effort to increase my water hardness. These 11 ghost shrimp live in my 5 gallon tank along with my betta. How much cuttlebone should I place in the filter and how often? I put a quarter-sized piece in there tonight and noticed that it dissolves pretty quick. How often should I add cuttlebone? Should I add it to the filter or just plop it in the tank? And either way - how big of a piece and how often? Thanks!