A recirculating seawater aquarium system for inland laboratories

We have designed and installed a 7,500 l recirculating aquarium system for the purpose of maintaining marine gastropods in an inland laboratory. It is completely nonmetallic and can be adapted for any number of isolated living compartments. Vonvenient and efficient filtration is achieved by the use of disposable cartridge filters. The water temperature is regulated by a direct expansion cooling coil and a hot water heating coil without the intervention of secondary heat transfer fluids. Most of the water is stored in an underground reservoir which contributes to thermal stability, and the water temperature varies <±0.1°C per week. The pH and specific gravity remain at 8.0±0.1 and 1.023+0.002-0.001, respectively, for as long as 4 months. We have no evidence that any animal (Aplysia, Hermissenda, Tritonia) has died due to poor water quality. The system is constructed from readily available components, is moderate in cost, and has performed reliably for over 2 years.