It’s generally a good idea to keep molted Wood Shrimp shells in a tank for a couple of days because other tank mates may nibble on the shells to re-ingest their minerals. This re-ingesting helps the shrimp get their bodies ready for their next molt. Softer molted shells from Ghost Shrimp, Amano Shrimp or Whisker Shrimp seem to be the easiest to re-ingest. Wood Shrimp shells are tougher, but can be re-ingested as well. This is especially true after a day or so when the shells start to dissolve and break apart. Mystery Snails, Gold Inca Snails, Ivory Snails and Ramshorn Snails also seem to be interested in ingesting bits of molted Wood Shrimp shells.
If after couple of days, none of the other tank inhabitants seem interested in the shell that remains, then its a good idea to gently remove the discarded shell before it breaks up into smaller pieces. Generally, the molted shells are harmless, but they can create a bit of an unsightly mess if allowed to litter the tank bottom. They can also get stuck in power filter water intakes as well.
Molted Wood Shrimp Shells On Tank Bottom
Sometimes Ghost Shrimp will pick through the inside of the molted wood shrimp shells, ripping off little bits of edible material that is attached to the interior surface.
Although it is probably pretty hard to see, there surely must be some edible material that forms a lining on the interior of the shell, because snails and shrimp seem to like it. They can pick and pull at it for hours on end.