The video shows a person conducting a water test in a fish tank. The person is holding a small vial containing a purple liquid and a white bottle with a red cap. The person is seen pouring the purple liquid into the water in the fish tank. The fish tank is filled with water and has various fish swimming around. The person is wearing a blue shirt and appears to be standing in front of the fish tank. The fish tank is well-lit and has a blue light on the top. The person is holding the vial with one hand and the white bottle with the other hand. The fish in the tank are of different sizes and colors. The person is seen pouring the liquid carefully into the water.