Although there are several ways to grow vibrant and lively aquatic plants, the Dirted Tank method is one of the best and most successful ones.
This simple method yields excellent results when it comes to adding more life to your aquarium. In our guide to the dirted tank setup, we’ll answer all your questions to help you get started.
So what is a dirted tank? How can you maintain your tank, and what are the most common problems that you’re likely to face?
Keep on reading to find out.
What is a Dirted Tank?
A dirted tank is where you use potting soil for your planted aquarium. The soil creates the perfect environment for your aquatic plants to grow and flourish. It’s a balanced environment where the fish and animals will complement the plants’ needs and vice versa.
Dirted tanks are low maintenance and suitable for beginners. They require minimal water changes and typically last for long.
What Is The Walstad Method?
This method is invented by Diana Walstad and is explained in detail in her book “ECOLOGY of the PLANTED AQUARIUM – A Practical Manual and Scientific Treatise for the Home Aquarist.” Diana Walstad is a known ecologist, and her method depends on creating a natural ecosystem.
In this tank, the fish and plants balance each other. The fish and bacteria produce carbon dioxide, which is later filtered by the plants. At the same time, the fish provide fertilizers that help the plants grow and flourish. This is a self-sustaining system that requires little intervention from a home aquarist.
The Walstad method has several aims;
- Good plant growth with little intervention.
- No or little algae that can affect the health of plants and fish.
- No need for injected carbon dioxide.
- No need for plant fertilizers.
- The system provides essential trace elements for the fish.
- Little need for frequent water changes.
- No need for a bio-filter because the plants will ingest the nitrate, nitrite, and ammonia, while the bacteria in the soil will feed on nitrogen.
Here is a great video from Father Fish where he explains exactly what a Dirted or Natural aquarium is. You better listen closely because there’s a whole lot of experience in what he is sharing.
How Do You Set Up A Walstad Dirted Tank
This closed ecosystem is based on the fact that plants and fish will cover each other’s needs. The substrate is made of fertile potting soil and capped with sand to grow plants faster and healthier. This mixture also reduces or eliminates algae and improves the nitrogen cycle in the aquarium. The setup is easy and suitable for beginners, and soon enough, your dirted tank will be a sustainable ecosystem where both fish and plants can survive.
- Add one inch of generic potting soil or organic soil, making sure that it’s free of chemicals. Chemical fertilizers are transformed into toxic substances when the soil is submerged in water, although calcium and phosphate fertilizers can be beneficial.
- On top, add a thin layer of sand or fine gravel. The sand shouldn’t totally cover the soil because the bacteria need to have access to the oxygen. Don’t add too many rocks or pieces of driftwood to keep the bacteria healthy.
- A calcium source can be mixed with soft water to cover the needs of the plants.
Adequate balance of light and darkness boosts the level of carbon dioxide that the plants need. In the first couple of months, the system needs proper filtration to enhance the levels of oxygen.
Until the soil is established, you’re likely to deal with high levels of ammonia, nitrate, and nitrite. This is why you need to test the water regularly. After a while, the system will work on its own, and the levels will subside, and eventually, these chemicals will disappear.
In the beginning, you might see algae growing. If this is the case, you need to reduce the exposure to light or add floating plants that compete with the algae.
You’ll have to do regular water changes to remove toxins and chemicals. After 2 months, the soil will stop producing nutrients that promote the growth of algae, and you can go longer between water changes.
You should wait for at least 2 months before adding any aquatic animals to the dirted tank. Algae-controlling organisms like feeder-shrimp can be added before introducing any fish.
Important Benefits Of A Dirted Tank
A dirted tank has a lot of advantages that make it appealing to any beginner or avid aquarist.
- The setup is easy because you can use aquatic or generic potting soil.
- The dirt provides a healthy environment that enhances the growth of roots and allows the plants to grow faster and healthier.
- Little or no fertilizers are needed to keep the plants healthy.
- Dirt releases tannin that protects your aquatic animals from harmful bacteria.
- This system requires little maintenance, so it’s an excellent choice for busy hobbyists.
Here Are A Few Pros And Cons Of Setting Up A Dirted Tank
Before you start setting up your dirted tank, you need to understand a little about the pros and cons of this closed ecosystem.
- This system is perfect for heavy root feeding plants.
- Potting soil is cheaper than aqua soil.
- The substrate will support your plants for long without any extra fertilizers.
- Your plants will grow fast and heavily in this system.
- The dirted tank requires less frequent water changes.
The Not So Good
- In the beginning, the system requires proper maintenance and constant attention.
- The initial algae bloom might be difficult to handle.
- Uprooting a plant will turn the water cloudy.
What Is The Best Soil For A Dirted Tank And Aquarium Plants?
Choosing the best soil for your dirted tank is the first step in setting up the system. Your plants need the right soil so that the roots can grow and have access to nutrients.
Different Aquarium Safe Soil Types You Can Use
The roots of your aquatic plants can’t hold onto the bottom glass surface; this is why you need to add the right type of soil to provide the necessary nutrients. The soil also contains useful bacteria that consume the toxic materials in the water to keep it healthy for your plants and fish.
There are several types of soil that you can choose for your dirted tank, and each one provides several benefits.
When used in a dirted tank, topsoil works well as it provides the plants with the right growth medium. However, topsoil comes with a few disadvantages that you need to take into consideration.
Topsoil is rich in organic materials that release nutrients. These nutrients will promote the growth of algae, at least for a few months. After the organic material in the soil has stopped breaking down, the growth of algae will be reduced until they’re completely eliminated. You can accelerate this process by decreasing the intensity of light.
Although garden soil is widely available, it might not be a good idea to use soil from your garden in setting up your dirted tank. Garden soil is rich in nutrients and organic matter because it contains traces of decomposed bugs and larvae that help the roots of plants grow.
However, when mixed with water, some types of garden soil turn to mud, so they will turn your water dark and cloudy. Moreover, garden soil might contain traces of insecticides or herbicides that can harm your aquatic plants and fish.
Before picking organic soil for your dirted tank, you need to do a little research to make sure that it’s suitable for your aquatic plants and animals. Perlite, surfactants, and vermiculite should be avoided because they will obstruct the growth of your plants.
If you choose 100% organic soil, your dirted tank will successfully sustain your plants and help them grow faster. Organic soil won’t contain any harmful additives or chemical fertilizers that affect the health of your plants.
If potting soil contains no additives or chemicals, you can definitely use it in a dirted tank. However, in most cases, potting soil contains fertilizers that release toxic chemicals in the water.
Potting soil has low drainage and might cloud your aquarium because the soil turns to mud. However, it can be safe for your aquatic plants, as long as you monitor the ammonia spikes during the first couple of months.
Can You Use Normal Dirt In An Aquarium?
The short answer is yes, although using organic soil is much easier. There are different substrate options that you can choose to grow plants in your aquarium, but soil provides the right nutrients that your plants need for rapid and continuous growth.
Adding normal dirt to your aquarium requires a little preparation. First, you need to handpick any foreign objects like twigs, stones, or insects. Then you need to sterilize the soil by sprinkling it on a baking sheet and baking it for about 20 minutes in the oven. This will kill any seeds or harmful microorganisms that can harm your plants or fish.
How Long Will Dirt Last In An Aquarium?
The answer to this question depends on a number of factors, including the mineral content of the dirt and the exposure to light. Moreover, the balance between the fish and plants in your dirted tank will have a huge impact on the efficiency of dirt used.
In most cases, the nutrients in the dirt will start deteriorating after a year or two, although you might be able to go for a few years without replacing dirt in your aquarium. The more plants you add to your system, the faster the dirt will lose the useful nutrients.
In general, if you have a heavily planted Walstad dirted tank, your dirt will last for about 2 years. After that, you can add root tabs to replenish the nutrients. However, in some cases, and if your system is well-balanced, your tank can go on for 5 years or even more without having to change the substrate.
Can You Use Coco Peat In Your Planted Aquarium?
Coco peat is made of the husks of coconut and is used as an alternative growing medium. However, coco peat isn’t the best substance to use in your dirted tank.
Coco peat will reduce the tannin in your aquarium, keeping the water fresh and clear. However, it should be topped with soil and sand to prevent coconut fibers from floating in the water. Coco peat lowers the PH level in your aquarium, but shouldn’t be used instead of organic soil.
Using Mushroom Substrate in Your Dirted Tank
Aquatic plants have different needs because you need to make sure that you’re not adding any toxic materials to your closed ecosystem. In general, organic soil is enough to provide the plants with all the needed nutrients, and there will be no need for any fertilizers.
Why Do Some People Use Worm Castings In The Substrate?
When the PH level of the soil is too high or too low, worm castings will act as a barrier to help plants grow. Worm castings or poop can be added to organic soil to increase the level of nutrients.
Can You Use Compost In Your Substrate?
Compost and other fertilizers are good for terrestrial plants. However, when used in an aquarium, compost will release methane gas, which is toxic to your fish.
Our Recommended Soil For use In Your Dirted Tank
Organic soil is the best recommendation for your dirted tank because it will provide all the necessary nutrients that help establish your tank. A high-quality organic soil should be free of chemicals and fertilizers. These chemicals would help plants grow faster but may be toxic to your fish.
Choosing the right soil for your dirted tank is the first and the most important step. Proper maintenance is needed for the first few months to fight off the growth of algae. Once the system has been established, it will be safe to add your fish.
Here Is An Example Of A DIY Aquarium Substrate Soil Mixture That Will Work Well In Your First Dirted Tank
The aquarium soil substrate should have enough nutrients to provide the roots of your plants with energy. Here is a DIY mix that you can prepare to set up your first dirted tank.
- Get some topsoil or organic soil and add water until it’s fully saturated.
- After soaking the water for 2 days, drain it. Soak the soil again for another 2 days and drain. Repeat the process several times.
- Spread the soil in a thin layer onto a wide container. Bake it to sterilize it or put it in the sun to make sure that it’s free from all contaminants.
- Handpick any twigs or rocks and sift the soil through a strainer to remove all the debris.
- Add one part of pottery clay to 10 parts of soil.
- Cover the bottom of your tank with Dolomite Lime to raise the PH level of the water. You can also add bone meal if you think that the soil doesn’t have enough nutrients.
- Put a layer of 1 to 2 inches of soil at the bottom of the tank.
- Cover this layer with gravel or sand.
How To Prepare Soil For Use In Your Aquarium
This depends on the type of soil you’ve picked for your tank. If you’ve chosen organic soil, you just need to take a look at the list of ingredients to make sure that it’s free from any hazardous chemicals. Garden and potting soil should be free from any fertilizers, herbicides, and insecticides. Sterilizing potting soil in the oven or in the sun will help eliminate the contaminants.
Capping Your Soil Substrate
Capping is adding sand or gravel on top of your soil substrate before adding the plants. It doesn’t add any real value to the plants, but it will keep the substrate in place.
What Is The Cap And Why Is It Important?
The cap is an inert material like sand or gravel. It has no nutrients, and the roots of the plant can’t grow in this material. Capping doesn’t mean covering the substrate completely, as you should leave some space to keep the substrate well-oxygenated.
Capping has a few benefits;
- It keeps the substrate in place and stabilizes the roots of the plant.
- It adds an aesthetic value to your tank.
- It prevents the clouding of the tank if you’re using potting soil that would otherwise get muddy.
What Is The Best Cap For A Dirted Tank?
One inch of capping material on top of your substrate would be enough to kickstart your dirted tank. There are several options that you can use to cap your substrate.
Using Sand As A Cap
You can add dark, colored, or white sand depending on your personal preferences. Plants love sand because it’s not too compact and won’t affect the oxygenation of the substrate underneath.
Using Gravel As A Cap
Gravel adds an aesthetic value to your dirted tank because there are several colors and sizes available. However, this might not be the best option for your dirted tank and aquatic plants.
Why A Sand Capped Soil Is Best
Sand is a better capping material when used in a dirted tank for the following reasons.
- Sand looks nice and natural.
- It’s easier to plant cuttings when you have sand.
- Sand is easy to rinse.
- Sand is available in different colors, so you can choose the one that would make the colors of your fish pop.
Planting Your Dirted Tank
After you’ve picked, prepared your substrate, and added the capping material, it’s time to add plants to your dirted tank. Simply add your plants to the substrate and then submerge your plants with water. Soon enough, the roots will grow and suck the nutrients from the soil.
The Benefits Of Using Plants In Your Aquarium
In addition to adding an aesthetic value, there are other few reasons why you should add plants to your aquarium.
- Plants improve the quality of the water in your aquarium. They prevent the growth of algae as they compete with them for the same nutrients.
- Plants utilize fish waste and uneaten food, thus preventing the water from becoming too cloudy or dirty.
- They provide natural hiding for fish to reduce stress, which enhances the color of fish.
- Plants help the fish feel more comfortable as they mimic their natural habitat. This encourages spawning.
- In daylight, plants produce oxygen and stabilize the PH level of the water. At the same time, they use the carbon dioxide produced by fish.
Further Reading: How To Keep Aquarium Plants Alive For Beginners
Low Tech VS. High Tech Dirted Tank
The terms high-tech and low-tech refer to the amount of light and nutrients in your aquarium. A high-tech dirted tank requires more effort as it involves using high-intensity lighting, daily added nutrients, and pressurized carbon dioxide injections. Moreover, regular water changes of 25% to 50% should be done weekly or bi-weekly.
A low-tech dirted tank is easier to maintain and take care of. The light used is medium to low, and no carbon dioxide is injected. Nutrients might not be added to the water, depending on the nature of the substrate.
Some high-maintenance plants like Dwarf Baby Tears will only survive in a high-tech tank. It has a lot of benefits because it enhances the rapid growth of plants and will boost their vibrant colors.
Low-tech tanks don’t require regular water changes. Nutrients can be added weekly, depending on the bioload of the tank and the total number of plants. A low-tech dirted tank is an excellent choice for beginners, as a high-tech one will take more time, effort, and money to maintain.
What Are The Best Plants For A Dirted Tank?
The following plants can easily grow in a dirted tank.
- Dwarf Hygro.
- Water Wisteria.
- Amazon Sword.
- Ludwigia Needle Leaf.
- Madagascar Lace Plant.
- Tiger Lilies.
Further Reading: Low Light Aquarium Plants That Are Easy To Grow
Cycling Your Dirted Tank And Why It’s Important
Cycling refers to establishing useful bacterial colonies to regulate the nitrogen cycle. Unless you take time to establish the population of useful bacteria, you won’t be able to control the ammonia level in the water, and your tank will be full of toxic nitrates and nitrites. Your tank will take between 1 and 2 months to be fully cycled.
Fishless Cycling A Dirted Tank
Cycling can be done with only 10% to 20% of your final fish load. However, a fishless cycle means that you can start cycling without any fish.
When you’re doing a fishless cycle, you must manually add ammonia to your dirted tank because there are no fish to produce the needed waste. Your bacteria will use ammonia for food, and when your filter is cycled, you can start adding fish to the tank. A fishless cycle would take time, but your fish won’t be at risk.
When Is It Okay To Add Fish
You can only put 10% to 20% of your final fish load into the tank, but they will be at high risk. If you’re going for a fishless cycle, you’ll need to wait between 4 to 6 weeks to establish your filter. It’s recommended to wait for at least 2 months before adding fish to your dirted tank.
Further Reading: How long do you need to wait before adding fish?
A lush, planted aquarium is an impressive sight, but adding a school of fish can take it to the next level. Learn how to choose the right species that will complement your underwater garden without disturbing the delicate balance of your ecosystem. Check out our top picks for the best schooling fish for planted tank and create a breathtaking aquatic display.
A Few Common Dirted Tank Problems Most Beginners Will Face And What To Do
Although a dirted tank is usually easy to take care of, there are some problems that you might encounter at the beginning. Here are the most common problems and how to fix them.
Water can become brown because of dissolved organic compounds. Brushing off the tank walls and giving the bacteria time to consume these compounds will help keep your water clear. Rub the algae off the leaves and increase the movement in the water. You can also use snails to feed on the algae.
Washing your substrate can prevent cloudy water. However, cloudy water can be the result of blooming bacteria, and the fog will eventually disappear when the cycling phase is over.
Inconsistent PH Levels
Adding alkaline and acidic buffers will help you keep the PH levels under control to protect your fish from excessive stress. Using carbon dioxide injections will help you regulate the PH levels.
Overfeeding your fish can cause ammonia spikes in your dirted tank. You might need to decrease the number of fish in the tank or do a 25% water change in addition to adding a biological filter. Ammonia levels are likely to be too high at the beginning when the bacterial colonies are still establishing themselves.
Further Reading: How To Reduce Ammonia In A Fish Tank Quickly
Having slow-growing plants or overstocking your tank can be the reason behind the high levels of nitrates. You can use an ion-exchanger to get rid of the problem.
You might feel that your dirted tank smells like rotten eggs. This is hydrogen sulfide, and adding more roots to the tank will solve the problem. Avoid overfeeding your fish because this will make the tank stink because it will promote the growth of anaerobic bacteria populations.
Bubbles From The Substrate
These bubbles could be carbon dioxide. In that case, you might need to give your plants time until they’ve consumed the carbon dioxide in the water. Add more plants if necessary.
Tannins and Dark Water
Tannins turn the water yellow or even brown. Tannins are not harmful to your fish unless they need a high PH level because they make the water more acidic.
Removing driftwood and changing the setup of your water tank will help decrease the initial amount of tannins. You can also add activated carbon to get rid of tannins.
How To Clean Aquarium Soil In A Dirted Tank The Right Way
A word of caution on this. In most cases, you really don’t want to do a deep cleaning of your dirted substrate it will remove all the good nutrients and bacteria that you waited so long to build up.
If you sand or gravel cap is dirty a light vacuuming is all you need.
That said, Vacuuming will work to clean your soil if it’s not too deep. This technique is performed using a special siphon that removes debris from the aquarium soil.
Lighter particles in your substrate like fish waste, uneaten food, and other organic materials will be sucked away, leaving your substrate in place.
If your tank is heavily planted, the roots might make the vacuuming process more challenging.
Further Reading: Python Water Changer
How Long Does A Dirted Tank Last?
With proper maintenance, a dirted tank can last for years. After a couple of years, you’ll have to use root tabs, and you can replace the substrates when you feel that the plants are not as lively as they used to be. As long as you do regular water changes, and keep the right number of fish in your tank, your dirted tank will last for a long time.
A Few Dirted Tank Tips That Will Ensure Your Success
Here are a few tips that will help your dirted tank succeed even if you’re a first-time aquarist.
- Always soak dirt before adding it to your dirted tank. Pack and cap it, then add water slowly to make sure that it’s not disturbed.
- If you have floating debris, empty the tank and fill it again until the water is clear.
- Pottery clay provides the needed iron to help establish your system.
- A couple of air stones will back up the oxygen production in your tank.
- Understock the tank until the system has reached a balance.
- Snails help to aerate the soil and keep the algae under control.
- Trim the plants and adjust the lighting to control algae growth.
- Once the fast-growing plants have been established, start adding slow-growing ones like Anubias.
- Adding too many algae eaters can actually cause more harm than good. Too many of them will cloud the water with their waste.
- Too much water flow can put your plants under stress and should be avoided.