Description: Negative Pressure Fish TankUsing the simplest principle of negative pressure in physics, the fish tank allows the fish in your aquarium to swimming upstream fly in the air.FeatureThe fish tank is also the automatic water replenishing device on the level of the fish tank, it will automatically add water to the fish tank as the water evaporates, keeping the overall water level of the fish tank constant.Increase Fish Activity AreaExpanded the viewing area and increased the fish's activity space, making the circulation of oxygen in the aquarium more efficient.High QualityFish tank is made of acrylic, which is sturdy, durable, and resistant to pollution, providing a clear view inside the aquarium for long time.Best ChoiceUse as a mini aquarium, desk terrarium, feeding box for small reptiles, etc. You can freely combine superimpose, very fun, the night view of the fish tank is very charming, you will have a fantastic fish tank. Specification: Material: Acrylic Size Chart: 19cmx13cmx12cm/7.48inchx5.12inchx4.72inch Package Includes: 1 Negative Pressure Fish Tank Note: 1. Please allow slightly error due to manual measurement.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item.3. Wish you a wonderful online shopping!