snipped from link below
Acclimating Snails, Crabs, Shrimp, and Starfish
Caution: Your Cleanup Critters are the most fragile during acclimation ( they are very sensitive to salinity and ph change), and need to be acclimated very slowly,
over a period of approximately two hours. Do not rush this procedure or losses will occur.
Acclimation Procedure: Snails, starfish, and other inverts are very sensitive to minor salinity and ph changes and must be slowly drip acclimated to insure their survival. Place invertebrates in a container and use a drip line to slowly acclimate all invertebrates. It is critical that invertebrates be slowly acclimated!! Drip acclimate at a rate of 1-2 drops per second for at least 2 hours.
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