What hardness and ph is your water? I have to do my first water change with the multi's. I did put Carib Sea live sand in with the pool sand when I set up their tank. They are in my water which is softened but I use both hard and soft water (soft water is on the hot tap) to do my water changes for all my other tanks and everyone is fine but I'm not sure if I should be using only hard water for the multi's? My water is very hard. Not sure exactly the number but it's very hard. What hardness is right for multi's. Or should I not be stressing about it so much as they have been living in my water now for over a week and they seem just fine.