How Do Goldfish Get Oxygen?

The Structure of the Gills

• The gills of the goldfish consist of very thin membranes, otherwise known as lamellae. The water has full contact with the fish's blood vessels, because the lamellae have a huge surface area. A goldfish has small gill flaps, through which the supporting structure of the gills is visible. The water opens the gills, while the fish is swimming. If, the goldfish is taken out of the water, its respiratory system will collapses, thus leading to suffocation.

How the Breathing Happens

• A goldfish takes in water using its mouth; once they close their mouth, the muscles in the throat contract and transfer the water over to the gills. This contraction dissolves the oxygen in the water. Afterwards, the dissolved oxygen enters the blood through diffusion. Diffusion happens during the movement of high-concentration soluble particles to a place with lower concentration. Water has higher concentration of oxygen compared to the blood flowing through the gills. This is how the oxygen from the water enters the blood. As this happens, the carbon dioxide leaves the blood and enters back into the water.

Oxygen Supply in the Water

• Air has more oxygen than water. This means oxygen in the air is broken down from the higher concentration to one of lower concentration, when oxygen molecules enter water and dissolve. Putting live fresh water plants in the goldfish bowl will stimulate the dissolving process of oxygen in the water by means of photosynthesis.

Caring for Your Goldfish

• Biologists classify goldfish as cold water fish. In fact, they benefit more from colder water because it can accommodate more dissolved gasses, such as oxygen. This fish can survive in water temperatures as cold as 65 degrees Fahrenheit. Stimulate the water movement in the aquarium to facilitate the elimination of carbon dioxide and increase the amount of dissolved oxygen.