How often should you change your aquarium water? This is one of the most common questions aquarium owners have. First of all, it doesn’t matter whether your aquarium is freshwater or saltwater. And it doesn’t matter if you have plants or corals.
How Often and How Much?We recommend changing at least 1/3 of your aquarium water once per month. This is a good minimum level of water changes to ensure you have a healthy aquarium.
What If You Want to Change Less Water?You can change less than 1/3 of your aquarium water at a time, but make sure the total of your water changes in a one-month period is 1/3 of your aquarium water. With a 60-gallon tank, you could change 20 gallons once per month, 10 gallons every other week, or 5 gallons every week, and you would satisfy the requirement to change 1/3 of your water every month. With small aquariums, a larger monthly water change is easy, but with larger aquariums, splitting the water changes into smaller weekly amounts is usually easier.
What Happens If You Change Water Less Than Once Per Month?We strongly recommend you change at least 1/3 of your aquarium water each month. Fish waste and uneaten food will start to accumulate in the aquarium gravel and filter. Sucking the waste out when doing a water change with a gravel vac is the best way to stop the waste from becoming an issue.
Additionally, chemicals can accumulate in the water over time. This can come from by-products in aquarium additives or minerals in the tap water used to top off the aquarium. Keep in mind that when the water evaporates, only the water is removed—all the minerals stay behind. If the water is never exchanged, the chemistry of the water will be out of range, causing problems for the health of your fish, plants, and corals.
Is It Useful To Change More Than 1/3 of The Water?Changing 1/3 of your water once per month is the minimum. It is very common for fish breeders or people medicating or conditioning fish to change water daily. We recommend changing no more than half of your aquarium water at a time to prevent the shock that can come from changing too much water at once. Always make sure that your new water is as close as possible to the same temperature, salinity, and pH of your old water.
Is It Sometimes a Good Idea to Do Large Water Changes?If your aquarium has an issue, such as an algae problem, or is very dirty from neglect, you may need to do more water changes for a time to get it back on track. Doing a series of 50% water changes daily to fix a problem is not uncommon. Keep in mind that an ounce of prevention is worth a pound of cure. Once the aquarium issue is resolved, you will no longer need to make water changes this large or this often.
