The stereotype of freshwater snails is that they are pests, destined to reproduce uncontrollably and overwhelm aquariums with a seemingly endless stream of babies. While this is certainly
true for a few snail species, there are also snails that are not only
beneficial but can also bring a new level of interest to your aquarium.
One such snail is the horned pagoda snail (Brotia pagodula).
While these snails may reproduce in an aquarium, they cannot do so
asexually like Malaysian trumpet snails, nor are they hermaphroditic
like ramshorn snails, meaning that you must have both males and
females in your tank for them to breed. While it’s practically impossible
to sex pagoda snails, this does mean that you’re somewhat less likely
to end up with offspring if you’re only keeping one or two snails. And
if you do end up with a breeding population, their reproduction will
be much slower and more manageable than the pest species.
Pagoda snails have a shell shape that makes them more interesting
than some other species. They are conical, kind of like a trumpet
snail, and grow to around 2 inches ( 5 cm). What makes them
appealing, though, are the spiraling rings of spikes that circle their
shell and are reminiscent of the Japanese pagodas after which they
Horned pagoda snails are native to Thailand, where they live in
fast-flowing streams, so you should keep them in an aquarium with
a decent amount of flow and fairly high oxygenation. They don’t
do as well as many other snails in more stagnant setups. You’ll also
want to keep them in moderately hard, slightly alkaline water. Like
other snails, the extra dissolved minerals (particularly calcium) will
help with their shell growth.
Horned pagoda snails are known to be somewhat reclusive,
preferring to be kept under subdued lighting. During the day
when the tank is brighter, it’s common for them to dig into the
substrate to hide. They will also search for food by sifting through
the aquarium substrate. This makes them a great choice for an
aquarium with a sandy bottom, as they will help to keep it well
mixed and prevent the buildup of toxic compounds that result in
anaerobic regions. However, they are also sensitive to these same
compounds, so you might want to thoroughly sift the sand to
remove any such anaerobic areas, particularly before adding the
snails for the first time.
These highly herbivorous snails will search for plant matter,
so if you don’t keep them well fed, this could include your
aquarium plants. Fortunately, they prefer to eat foods that are very
easy to break up into tiny pieces, so they will readily consume
commercially available algae and herbivore foods, including pellets
and wafers. You can also feed them fresh or cooked vegetables to
discourage them from going after your plants.
Horned Pagoda Snail (Brotia pagodula )
Most of the time when aquarists speak about pom pom crabs, they are referring to the marine species (Lybia spp.) that carry anemones in their claws for defense,
camouflage, and food collection. However, a similar freshwater
variety is also available. Much like the marine crab’s anemones, the
freshwater pom pom crab (Ptychognathus barbatus) has hairy tufts
resembling algae on its claws that it can use to sweep up food, and
these crabs can be fed like vampire shrimp by offering tiny food
options that are carried with the water current.
In many ways, freshwater pom pom crabs have similar care
requirements as Thai micro crabs. While they are a touch larger and
more robust than micro crabs, they are very small (rarely exceeding
a 1½-inch [4-cm] leg span) with no real methods of defense, making
it important to carefully choose tankmates that won’t eat them and
to provide plenty of cover for them to hide in. Some freshwater pom
pom crabs have been known to be persistent in their attempts to
escape their aquariums, so make sure you have a tight-fitting lid,
and maybe keep your water level somewhat lowered.
Freshwater pom pom crabs seem to do well in soft and slightly
acidic conditions. Aim for a pH ranging from low 6s to low 7s and
a temperature somewhere in the 70s F (low- to mid-20s C). So far,
there have not been any confirmed reports of successfully breeding
freshwater pom pom crabs that we can find. It’s hypothesized that,
like certain shrimp and snails, they primarily live in freshwater but
migrate to brackish or marine environments when it’s time to breed.
Pom Pom Crab (Ptychognathus barbatus)