How to Add or Change Substrate in an Established Aquarium
Changing or adding substrate to an already established aquarium doesn’t have to be a difficult task. With the right preparation and care, you can successfully upgrade or refresh your tanks substrate without disturbing your plants, fish, or water balance. Whether you’re adding a nutrient rich substrate like aquasoil or simply refreshing your existing substrate.
Here’s everything you need to know to make the process go smoothly:
1. What Is Substrate in an Established Aquarium?
Substrate is the material that covers the bottom of your aquarium, these substrates could either be inert, like sand or gravel, which means they don't affect the water's chemistry, or nutrient-rich, like aquarium soil, which provides essential nutrients for plants to grow, in an established tank substrates serve several vital functions.
These include:
Supporting Plant Growth:
A healthy substrate supports the growth of plant roots.
Aids in Filtration:
Beneficial bacteria colonise the substrate and help break down waste.
Affects Water Chemistry:
Some substrates like aquasoil can lower pH and soften water, which can be beneficial for certain plants and fish.
Enhances Aesthetics:
Changing or adding substrate can enhance the look of your aquarium, whether you’re aiming for a natural or ornamental aquascape.
2. Why Changing or Adding Substrate can be Important for Your Aquarium
Adding or changing substrate can improve plant health, create a more stable environment for fish and give your aquarium a fresh look!
Replenishing or changing substrate can provide:
Healthy Plant Growth:
Adding a nutrient-rich substrate like aquasoil can greatly improve root development and plant growth, especially for heavy root feeding plants such as Amazon Swords.
Improved Filtration:
A well-maintained substrate supports the growth of beneficial bacteria, which helps with biological filtration and maintaining a clean tank.
Stabilized Water Chemistry:
Some substrates can help stabilize pH and water hardness, providing optimal conditions for both fish and plants.
3. Preparing the Substrate
Before adding substrate to your established tank, you need to properly prepare it to avoid disturbing your aquarium's ecosystem.
Here’s how to get started:
1. Gravel Substrates:
Step 1: Fill a Bucket/Container with Your New Substrate.
- Tip: Place your new substrate (e.g., gravel) into a clean bucket.
Step 2: Fill the Bucket/Container with Water to clean off all the dirt and debris using your hands.
- Tip: Use high-pressure water from a hose to easily dislodge dust and debris while gently moving the substrate around with your hands. Be careful not to use too much pressure, as it could blast the substrate away.
Step 3: empty the water out of the Bucket/Container.
- Tip: Keep emptying the water and refilling until all the dirt and debris are gone, and the water runs clear. This may take a few rinses, so be patient!
- Pro Tip: When emptying the water, try to pour it out slowly and carefully to avoid spilling any substrate. You want to keep as much of it as possible for your aquarium.
Step 5: your substrate is ready to go into your aquarium! Skip to chapter 4 for further information.
2. Sand Substrates:
Step 1: Fill a Bucket/Container with Your New Substrate.
- Tip: Place your new substrate (.e.g., sand) into a clean bucket.
Step 2: Fill the Bucket/Container with Water to clean off all the dirt and debris using your hands.
- Pro Tip: Always wash your sand thoroughly before adding it to you aquarium. Place the sand in a bucket and rinse it with water over and over until the water runs clear. This will help prevent cloudiness in your tank when it’s added.
- Hint: Pool filter sand or play sand is ideal for aquariums. These types of sand are fine and smooth, making them great for bottom dwelling fish like catfish, and they’re usually more affordable than aquarium sand you can find at retail stores.
Step 3: empty the water out of the Bucket/Container.
- Tip: Keep emptying the water and refilling until all the dirt and debris are gone, and the water runs clear. This may take a few rinses, so be patient!
- Pro Tip: When emptying the water, try to pour it out slowly and carefully to avoid spilling any substrate. You want to keep as much of it as possible for your aquarium.
Step 4: your substrate is ready to go into your aquarium! Skip to chapter 4 for further information.
3. Nutrient Rich Substrates:
Step 1: Fill a Bucket/Container with Your New Substrate.
- Tip: Place your new substrate (e.g., aquasoil) into a clean bucket. If you're using aquasoil, it’s a good idea to layer a plate, bowl or saucer on top before adding water to prevent the water from disturbing the substrate when adding it, if the water is too strong on the substrate it can cause it to go muddy.
Step 2: Fill the Bucket/Container with Water.
- Pro Tip: Fill the bucket with water and let it sit for 24 hours. The water will become cloudy from the aquasoil, but this is normal.
Step 3: Test for Ammonia.
- Hint: Aquasoil and other nutrient-rich substrates can cause ammonia spikes when first added to the water. Use a test kit to check ammonia levels, and don’t be alarmed if the levels are high, this is completely normal!
- Pro Tip: Use a water conditioner like Seachem Prime to neutralise ammonia and detoxify the water during this phase.
Step 4: Monitor the Ammonia Levels.
- Tip: Perform water changes on the bucket/container regularly and test the ammonia levels daily or weekly, depending on your preference. Once the ammonia levels drop to safe levels (close to 0 ppm), you're ready to move on to the next step!
-
Pro Tip: This process can take 6-8
weeks of water changes, so it's a long journey, but it's worth it. Taking the time to get it right will ensure your fish and plants stay safe and healthy in the long
run.
4. Preparing Your Aquarium
Once your substrate is prepped and the ammonia levels are under control, it’s time to prepare your aquarium.
Step 1: Remove Sensitive Plants and Decorations.
- Pro Tip: If you have delicate plants or decorations, gently remove them from the tank to avoid disturbing them during the substrate change.
Step 2: Vacuum Existing Substrate to Remove Debris (or if your doing a complete change you can syphon the substrate out).
- Tip: If you are only adding a new layer of substrate, use a gravel vacuum to clean any debris from the existing substrate. This ensures that waste and organic material are cleared before adding new substrate.
Step 3: Adjust Water Parameters if Necessary.
- Hint: If you’re using aquasoil or a similar substrate that can lower pH, make sure your water parameters (pH, hardness, and temperature) are in an acceptable range for your fish and plants.
5. Adding the Substrate
Now that both your new substrate and aquarium are ready, you can begin adding the substrate.
Step 1: Add the Substrate Gently.
- Tip: Start by adding the substrate slowly, one scoop at a time, this can be done scooping the new substrate with a bowl or cup and gently placing it into your tank just above your existing substrate and spreading it out. If possible, avoid dumping it directly into the water to reduce cloudiness and ammonia spikes.
Step 2: Layer Your Substrate.
- Pro Tip: For a nutrient-rich substrate like aquasoil, aim for a 5-7 cm layer. This will provide enough depth for plant roots to establish themselves and thrive.
Step 3: Position Your Plants.
- Hint: After adding the substrate, gently place any plants back into the tank and ensure they are securely anchored in the substrate. For heavy root feeding plants, make sure they’re placed where they’ll have ample access to the nutrients in the substrate.
6. Option to Completely Strip the Tank
If you want a completely fresh start, you can strip the entire tank down and replace all the substrate. This method is ideal if you’re upgrading to a new substrate or want to remove old substrate that has depleted its nutrients.
Step 1: Remove Fish and Plants.
- Tip: Carefully remove all fish from the tank and place them in a temporary holding bucket, tank or container with water from the aquarium to prevent stress and keeping the fish healthy. Do the same with plants that you want to keep as well.
Step 2: Remove the Old Substrate.
- Pro Tip: If you're completely replacing the substrate, remove the old substrate entirely. You may want to vacuum the bottom of the tank to ensure that no waste or debris is left behind.
Step 3: Clean the Tank.
- Tip: This step isn't all that necessary, but now the tank is completely striped, theirs no better time to give it a good deep clean before setting it back up again!.
- Hint: Clean the aquarium glass and decorations with a sponge or scraper to remove any algae or build up. Avoid using soap or chemicals, as these can harm your fish when you add them back into your aquarium.
Step 4: Add the New Substrate.
- Hint: Follow the previous steps to prepare and add the new substrate. This is the ideal time to set up a fresh layer of aquasoil, sand, or any other substrate of your choosing.
7. Monitor Water Quality
Once the new substrate is in place, it’s essential to keep a close eye on your water quality to ensure that everything goes smoothly and parameters stay within a healthy range for when you add your fish back in.
Step 1: Test Water Parameters.
- Pro Tip: Test the water regularly for ammonia, pH, and nitrate levels. Nutrient rich substrates like aquasoil can cause temporary ammonia spikes, so keep track of water quality.
- Hint: This is why i suggested to do the Bucket/Container method earlier, doing this method over the course of a few days is so water quality will stay stable when you add the substrate into your established aquarium.
Step 2: Perform Water Changes.
- Tip: Regular water changes (20-30%) will help maintain optimal water quality and dilute any ammonia or other pollutants that might be present within the water column.
Step 3: Watch Your Fish and Plants.
- Hint: Keep an eye on your fish and plants for any signs of stress. If your fish appear lethargic (sitting on the bottom of the tank, or gasping for air at the surface) or are showing signs of distress (such as darting/flashing, scratching a lot or seem scared), it may be a sign that the water parameters aren’t quite right, and you may need to test your parameters adjust them by doing necessary water changes.
8. Final Touches and Long-Term Care
Once your substrate has settled and water quality is stable, you can enjoy the benefits of a refreshed tank.
Step 1: Add Fish Back (If Removed).
- Tip: If you removed fish for the substrate change, now is the time to carefully reintroduce them to the tank!. Be sure to do this gradually though, especially if your water parameters have changed significantly.
Step 2: Fertilise if Needed.
- Pro Tip: If you're using a non nutrient substrate like gravel, remember to add root tabs or liquid fertilisers to help your plants thrive!
Step 3: Ongoing Maintenance.
- Hint: Continue to monitor your water parameters and maintain your tank regularly. Nutrient rich substrates like aquasoil may need the occasional replenishing as they deplete over time.
9. Conclusion
Changing or adding substrate in an established aquarium can be a straightforward process when done with care and preparation. Whether you're improving plant health with a nutrient rich substrate or simply refreshing the look of your aquarium, following the right steps will ensure a smooth transition and a happy, healthy aquarium! With proper monitoring, water quality management, and attention to detail, your tank will thrive for years to come!
- Pro Tip: If you’re new to adding substrate, start with a nutrient-rich substrate like aquasoil for the best results. As you gain experience, you can experiment with different substrates or combinations to find the perfect fit for your aquarium.