Mechanical and chemical water filters for use in aquariums; water heaters for use in aquariums; water sterilizers for use in aquariums; strainers for plumbing drains for use in aquariums; plastic/glass plumbing fittings, namely, couplers, traps, adapters, bulkheads, and valves for use in aquariums; decorative lighting fixtures for use in aquariums

Refractometers