Many beginning hobbyists think snails are essential as scavengers, only to find that some red ramshorns, after a day or two in the tank, will get their antennae nipped by fish every time they poke their head out, and eventually starve inside their shell. It’s one of life’s ironies that if you want to keep snails they seem to be easily killed off, and if you don’t want them they multiply like crazy.

Most snails do best in harder/alkaline water. If the hardness/pH drops below a certain point, their shells will start to dissolve and/or grow improperly. Malaysian trumpet snails seem the hardiest, showing little adverse effect from soft water. The Ramshorn snails shell will start to dissolve, and gaps will form in the new shell growth. Mystery snails will form gaps. Most of these problems can be corrected by hardening the water, and the snails will recover, although exterior shell damage from dissolving will remain. Here are four popular species:

Ampullaria or Pomacea (Mystery or Apple snails):
If you’re breeding fish, this snail provides some great advantages. However, there are at least four distinct species of Ampullaria, three of which are ravenous plant eaters and should be kept out of planted aquaria. All are sometimes known as infus ...

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