Exceptional Quality - Unbeatable Prices

How Often Should You Change Aquarium Water?

How Often Should You Change Aquarium Water

Water changes should be part of your regular aquarium maintenance, even if your water looks clear. The frequency will vary depending on many factors.

Water changes should be part of your regular aquarium maintenance, even if your water looks clear. When fish are fed, particles of food fall to the tank bottom where it will decay. The food that is eaten is eventually released back into the water as urine or feces, which also adds to the debris that will sit on the bottom of your tank.

The frequency will vary depending on many factors. Smaller, heavily stocked tanks will require more frequent water changes than larger, sparsely stocked aquariums.

Invisible waste by products will build up in the form of nitrates and phosphates. This can put stress on your fish, making them vulnerable to disease. If you have elevated nitrates it could stunt the growth of young fish and interfere with normal reproduction in adult fish. Nitrates also will promote overgrowth of algae. Phosphates will have a similar effect. Changing the water frequently is the best way to keep nitrate and phosphate levels low.

Wastes are not the only reason water needs to be changed. You will have trace elements and minerals in the water which are important to the health of your fish as well as the stability of the water. If they are not replaced, your pH of the water will drop. The lack of trace minerals will eventually affect the health of the fish.

Change 10 to 15 percent of the water each week. If your tank is heavily stocked, bump that up to 20 percent each week. A lightly stocked tank can get by for two weeks, but that should be the maximum length of time between water changes as you do not want to place any stress on your fish.


What about topping off?

Many people think that if they add water to the tank, it is the same thing as changing the water. Adding water does not remove any of the wastes and this will affect your levels.


Here are a few tips

  • Allow the water sit for a day this will dissipate dissolved gasses or chorine and allow the pH to stabilize.
  • When doing a water change, you should vacuum the rocks and the bottom of your tank. Get rid of some of the detritus that is building up.
  • You should not clean the gravel and the filter on the same day. Both of these have beneficial bacteria that are good for your aquarium. Do not disrupt both locations at the same time. Do your filter cleaning so it takes place on a day that you are not changing water and vacuuming gravel.


Any other questions feel free to contact us at Melbourne Tropical Fish, 41-43 Sinclair Rd Dandenong VIC 3175.


Contact Us

Melbourne Tropical Fish

Factory 2/41-43 Sinclair Rd

Dandenong VIC 3175

(03) 9792 5513


Leave a comment

Please note, comments must be approved before they are published