Buzz
Regular water changes are crucial for maintaining and caring for a freshwater aquarium. Changing part of the water allows you to better control the levels of dirt and toxins in the tank. To perform a water change, you should have clean water ready and remove the dirty water from the tank. You can also clean the substrate and remove algae from the tank walls before gently adding fresh water without disturbing the fish, leaving you with a clean and beautiful aquarium.
Steps
Preparing for the Water Change
Pre-treat a bucket of tap water. Take a clean bucket, fill it with tap water, and follow the instructions on the water conditioner bottle to purify the water. The water conditioner will remove harmful chemicals and metal residues, making the water safer for your fish.
- It is recommended to prepare two plastic buckets dedicated solely for aquarium use. You may even label them with the word “fish” for easy identification.
- Some people prefer using tap water directly for the aquarium water change. While more convenient, this could expose the fish to harmful chemicals. To reduce this risk, let the faucet run for about five minutes before filling the bucket with water.
Turn off the lights and heater. When maintaining the exterior of the aquarium, it is best to limit contact with electrical sources. Start by removing the aquarium lid and lighting system, then unplug the heater.
Unplug and clean the filter system. Many aquarium filters do not function effectively without water, so it is advisable to unplug the filter when you begin cleaning the tank. You don’t need to clean or replace the filter cartridge, sponge, or other filter components every time you clean the tank. Instead, inspect the filter and rinse it under cold water or replace it with a completely new one if necessary.
- Replacing the filter too often is not ideal for your aquarium, as it will also remove beneficial bacteria. To maintain balance, consider adding a layer of gravel or sand with beneficial bacteria when installing a new filter.
Remove dirty plants and decorations from the tank. Each time you change the water, you should also clean the tank's decorations. While this may impact the beneficial bacteria in the tank, if the artificial items are slimy or covered in mud, you should gently place them in a bucket and soak them in vegetable wash water.
- Do not wash plants and decorations with soap. Chemical residues can harm the fish and promote algae growth.
- You can also soak plants and decorations in a chlorine remover solution. For each bucket of water, add 1-2 tablespoons of chlorine remover.
Scrub the tank walls. Whenever you change the water, check if the tank walls need scrubbing by looking for green or brown films. When the tank is still full of water, use a sponge or brush to scrub the walls and remove any dirt or buildup.
Doug Ludemann
Professional aquarium enthusiast
Professional aquarium enthusiast
You can add lanthanum chloride to the aquarium to remove phosphate – the substance that promotes algae growth. Lanthanum chloride is a molecule that binds phosphate molecules into an insoluble compound. This compound will cloud the water, and you will need to filter the water to remove it, or else it will remain in the tank. However, if you manage to eliminate this compound, it means you will also be removing the phosphate.
Start the water change process
Use an automatic water changer. This is one of the most effective and popular methods for changing part of the water in an aquarium, especially for larger tanks. You will attach the device directly to the faucet, then insert one end of the hose into the tank. The device will automatically siphon water out of the tank until you turn it off. Afterward, turn the device back on and connect the hose to the faucet to pump water back into the tank.
- This method is particularly useful for those who cannot carry water to clean the tank regularly and helps prevent overflow.
- Make sure the new water you add to the tank is at a similar temperature to the water in the tank. Check this before you start the automatic water change process.
Siphon debris from the substrate using a gravel vacuum. If you don’t have specialized equipment, you will need to manually change the water. Start by placing one end of the hose into a bucket, and then insert the other end into the substrate in the tank, typically gravel or sand. Move the hose around to suck up debris and water.
- You don’t have to completely clean the substrate each time you change the water. In fact, it’s better to divide the tank into different sections and only clean one section at a time. This helps minimize the impact on the fish.
Siphon water out of the tank. As you move the siphon hose around the tank, you will see the debris and cloudy water starting to flow into the bucket. This is completely normal, but you should only siphon out up to 30% of the tank's water. Going beyond this amount can upset the balance of the tank’s environment.
- For example, if your tank holds 40 liters, use a 12-liter bucket for the water change. This way, when the bucket is full, you’ll know you’ve removed the appropriate amount of water.
Carefully inspect the inside of the tank. Now that the water level in the tank has lowered, take some time to observe the interior to check the tank's condition. If there are any decorations still in the tank, you should pick them up to see if they are damaged and also check that the heating and filtration systems are functioning properly.
Record the water temperature in the tank. If a thermometer is attached to the tank, note the temperature of the water after you have removed part of it. If not, you can submerge a thermometer into the water to measure the temperature, then check the temperature of the treated water you are about to add. Ensure that the temperature of the tank water and the water you are adding are the same. If they are not, you will need to wait a bit before adding the new water.
- Temperature changes can make fish more susceptible to illness. You should measure the water temperature again after adding the treated water to the tank.
Add treated water to the tank. Now, pour the treated water from the bucket into the tank. You can use a jug or a ladle to scoop the water or lift the bucket with both hands and pour it directly into the tank.
- Whichever method you choose, ensure you don’t pour the water too quickly to avoid disturbing the substrate and decorations. Many people use their hands or a plate to slow down the water flow into the tank.
Return all decorations and plants to the tank. If you removed decorations from the tank earlier, you can place them back in the tank either before or after adding the water. You may also choose to rearrange or completely remove the decorations to create a completely new tank layout.
Turn on the filtration system, heater, and lighting. Now, you can switch all the devices back on that you had previously turned off when preparing to change the water. Ensure that your hands are dry and proceed with caution as you reinstall and power up these devices. For some filter systems, such as hang-on-back filters, you may need to pour 1-2 cups of water directly into the system to get it ready to work.
Clean and store the cleaning tools. Designate a specific area for storing your aquarium cleaning tools. Before putting them away, make sure the bucket, brush, and siphon are completely dry. Proper storage will help you extend the lifespan of your equipment and reduce the need for replacements.
Maintain a long-lasting clean aquarium
Change a portion of the water weekly. It is recommended to change the water regularly every week or every two weeks. Each time, replace around 25-30% of the water in the tank. If necessary, you can do a complete cleaning and water change on a monthly basis.
- Find a balance between maintaining tank cleanliness and ensuring the health of the fish. Over-cleaning or under-cleaning the aquarium can both negatively impact the fish's well-being.
"Reset" the tank by changing the water. Changing a portion of the water can also be an effective way to restore the tank's stability after incidents such as shocks or chemical overdoses. Even if it’s not on the regular schedule, consider performing a water change after such events.
Limit the use of lights. If you keep the aquarium lights on all day, you may notice that algae grows and dirt accumulates faster. This is because light helps algae absorb nutrients from the water. Instead of keeping the lights on all day, it is better to limit the lighting to 10-14 hours a day for tanks with live plants, or 6-10 hours for tanks without plants.
Avoid overfeeding the fish. Most of the debris sucked from the substrate consists of leftover fish food. To prevent this, only feed the fish once or twice a day and adjust the amount of food based on how quickly the fish consume it.
Tips
- Many aquarium owners find it helpful to keep a maintenance log to record the date, amount of water changed, and any important observations you come across.
- You can use the dirty water removed from the tank to water plants.
- As you gain experience, you will become quicker at performing water changes. In fact, once you're familiar with the process, you may even be able to clean large tanks in under an hour.
Warnings
- If you overcrowd the tank with too many fish, you will need to clean the tank more frequently.
Items You Will Need
- 2-3 plastic buckets (10L each)
- Water faucet nozzle
- Automatic water change device (optional)
- Brush
- Dechlorinator solution
- Fish tank debris siphon hose
- Filter box or replacement tools
- Paper towels (optional)
- Chopsticks (optional)
- Watering can or plate (optional)
