Help! I'm losing my cherries!

I have extremely low GH & KH and dropped a cuttlebone in the tank. They were fine without it for a month or so, but I decided to add it after continued reading. May be worth a try to help them through molting.
 
another thing you could try would be to make plaster discs to help. You take home depot brand plaster of paris (it doesn't have additives) and mix it thick, spoon into an ice cube tray, let set for a couple of days, then pop out and add to either your filter, or a low flow spot in your tank. You can also add some food to the plaster (low oil/fat or they dissolve quickly) to make it a feeder.
 
Yep, just the ones sold for birds. You can boil it to get it to sink immediately or float it for a week or so and it will gradually sink.
 
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