Tank Setup: The aquarium architecture must reflect their estuarine, bottom-dwelling nature. A minimum 40-liter (10-gallon) tank is required.
CRITICAL SALINITY REQUIREMENT: This is absolutely NOT a freshwater snail. They unconditionally require heavy brackish to full marine (saltwater) setups (Specific Gravity 1.015 - 1.025). The substrate MUST consist of deep, soft marine sand or mud. They do not require a tight lid, as they rarely climb glass, preferring to endlessly bulldoze the sandy bottom.
Diet and Feeding: They are ravenous, highly effective detritivores and benthic diatom specialists. They DO NOT consume large macroalgae or seaweed. Instead, they spend their days vacuuming the sand bed, consuming microscopic diatoms, cyanobacteria, decaying organic matter, and uneaten fish food. In the aquarium, their massive appetite must be fueled by a mature, "dirty" sandbed. If the tank is too pristine, they must be supplemented with sinking omnivore pellets and powdered spirulina.
Water Quality: Originating from the tidal flats of the Pacific, they are incredibly adaptable to temperature swings. They easily tolerate cool to warm water (15-26°C / 59-79°F). However, their survival is entirely dependent on water chemistry. They absolutely CANNOT survive in freshwater; placing them in a freshwater tank will cause immediate osmotic shock and rapid death. They strictly require hard, alkaline marine or heavy brackish water (pH 7.8 - 8.4) rich in oceanic calcium and magnesium to maintain their thick shells.
Compatibility and Tankmates: Compatibility is excellent for brackish or marine tanks, provided they are not housed with dedicated shell-crushers. They are the perfect, indestructible cleanup crew for saltwater mudskipper tanks, brackish Pufferfish tanks (if the puffers are small enough to ignore their thick shells), or peaceful reef sumps. They completely ignore fish and shrimp. They MUST NOT be housed with massive, aggressive marine Hermit Crabs or large Wrasses that possess the jaw strength to crush their shells.
Aquarium Breeding: Breeding *Batillaria zonalis* in a standard home aquarium is highly complex. While they will mate and females will lay eggs, the eggs hatch into microscopic, free-swimming veliger larvae (plankton). These larvae require highly specific, fluctuating marine salinities and immense amounts of microscopic phytoplankton to survive their complex metamorphosis into juvenile snails. Consequently, they will almost NEVER successfully reproduce or overpopulate a home aquarium.
Risks and Diseases: The absolute greatest physical risk is instantaneous, agonizing death from osmotic shock caused by owners mistakenly placing this marine/brackish species into a standard freshwater aquarium; heavy salinity is unconditionally mandatory. The second major risk is slow starvation in pristine, newly established, "sterile" saltwater tanks that lack a mature sandbed rich in diatoms. Finally, they can be crushed and eaten by large marine predators if housed incorrectly.