... 2)Water doesnot need to be changed 3)Automatic filtration&ventilation 4)Constant temperature 5)3C&CE New pet product--Fish tank ... *62cm Packing bubble and cartonFactors 1. electrical safety , 2. constant temperature & heat preservation, 3. without changing ... the water, 4. automatic filtration, 5. automatic ventilation, 6. clean convenience, 7. peculiar illumination, ...