Abstract: An aquarium includes: a box having an accommodating space therein; a dividing board disposed in the accommodating space of the box to divide it into a cultivating layer and a nitrobacteria layer; a pump for drawing water and air, mixing them into bubbles, and sending the mixture out via a transporting pipe; a foam remover connected with the transporting pipe and having a foam outlet and a water outlet. The bubbles received from the transporting pipe are broken into smaller bubbles in the foam remover. The protein impurities in the water are expelled with the bubbles via the foam outlet. The processed water flows via the water outlet into the nitrobacteria layer to decompose the proteins.

Abstract: An aquarium includes: a box having an accommodating space therein; a dividing board disposed in the accommodating space of the box to divide it into a cultivating layer and a nitrobacteria layer; a pump for drawing water and air, mixing them into bubbles, and sending the mixture out via a transporting pipe; a foam remover connected with the transporting pipe and having a foam outlet and a water outlet. The bubbles received from the transporting pipe are broken into smaller bubbles in the foam remover. The protein impurities in the water are expelled with the bubbles via the foam outlet. The processed water flows via the water outlet into the nitrobacteria layer to decompose the proteins.