A self-sustaining aquarium is one where the ecosystem is so established that it doesn’t require constant care from another person.
The idea is that everything in the aquarium is supporting each other. It would require minimal input from the person and give minimal output as well.
Understanding Self-Sustaining Aquariums
Now, creating a self-sustaining aquarium is not an easy task. You will need a fairly good understanding of biology, run regular checks and know how to balance the cycle in the tank if it gets out of hand. Plus, during the start, you will have to be very hands-on.
Once the self-sustaining cycle is established, you won’t have much to do apart from the regular checks and maintenance.
Before you begin though, it is time to take a closer look at the main concept of a self-sustaining aquarium.
The Walstad Method
The concept of a self-sustaining aquarium is not a new one but it was brought to light properly by Diana Walstad. A trained microbiologist, Walstad published her first book, Ecology of the Planted Aquarium in 1999. In her book, she talked about a self-sustaining cycle for planted aquariums.
The Walstad method made waves in the aquarium hobby community as many aquarists applied the steps outlined and found the tank methods to be true. The best part is that you can still read the book today and learn from its teachings.
The book has helped many hobbyists understand what goes on in their aquarium and how they can maintain and look after a self-sustaining aquarium.
The good news is that this method can be applied to any fish tank. However, hardy species like Betta fish will benefit more with this option.
The Aim of a Self-Sustaining Aquarium with the Walstad Method
The major principle behind the Walstad method is to create an ecosystem where the plants and the fish are able to balance their needs harmoniously.
The belief is that the substrate soil will provide plants with nourishment by recycling all the toxins and fish waste.
The plants will filter and clean the water, giving the fish a cleaner, healthier environment to live in.
Additionally, the fish will create waste which is necessary for the health of the plants. In this way, the aquarium will enter into a self-sustaining cycle where each party benefits.
Other aims of a self-sustaining aquarium include:
- Healthy plant growth
- No need for CO2 injections
- Little to no growth of algae
- No plant fertilizers required
- Improves fish health
- Gives a stable environment to the fish
- Eliminates the need for substrate vacuuming
- Doesn’t require water changes frequently, especially once the cycle is established
- No smell or requirement for bio-filter
A healthy self-sustaining aquarium is one that is able to meet all these aims. While it might seem impossible at the start, the Walstad method can make it possible to do this.
Set up Items Needed for Your Tank
To follow the Walstad method, you need to focus on the setup. This will be considerably different from what you would get traditionally. The following are the items you will need to set up the tank:
- Aquarium – 20 gallon or larger
- Substrate – Topsoil – the generic gardening variety – Walstad recommends the No. 3 soil-based compost variety from John Innes
- Substrate – Fine gravel – Can also use sand
- Plants – As many as you like – Walstad recommends a heavily planted tank with low light and floating plant varieties
- Invertebrates – Nerite snails and Amano shrimps
- Filter – None – the belief is that the plants will function as biological filters here
- Lights – Get lighting for 2w per gallon. The tank relies on proper lighting and you will have to leave it on for 10 hours at least.
- Heater – Yes – While the traditional Walstad tank is meant to be at room temperature, Betta fish need to be kept at 78oF to 80oF (25.5oC to 26.5oC).
- Fish – Betta fish
Steps for Setting Up the Tank for Betta fish
Once you have all the items, it is time to set up the tank.
Setting up a self-sustaining aquarium has to be done with care. Poor setup can mean that it will take longer to get established.
Nonetheless, the following are the steps you should take for setting it up:
Filtering the Compost
Use an old kitchen sieve and add a cupful of compost to it. Shake it until you get a refined, cleaner powder.
This is done to remove any impurities or items such as twigs, stones or even insects. This will also give you a finer compost to use for your tank.
If you don’t have a sieve, use some chicken wire stapled across a box and pour the compost into it. Make sure to wear gloves and stir the compost around to get rid of all the impurities.
Wash the Gravel or Sand
Next, you have to wash the gravel or the sand that you are planning to use. These can contain small impurities as well so these have to be removed. To wash the sand or gravel, soak it in some water and leave it overnight.
In the morning, you should change the water and then see if any impurities surface. If they don’t, the grave or sand is ready for use and can be added to your tank.
Prepare the Plants
Since the plants are going to be functioning as the bio-filter for the tank, make sure that you have plenty of them available. The following are some great plants that you can add to your tank:
- Moss – Subwassertang, Java moss or Marimo moss balls
- Rhizome Plants – Java Windelov Fern, Anubias Coffeefolia
- Rooting Plants – Amazon sword and Vallisneria Spiralis Leopard
- Stem Plants – Anacharis densa, Rotala Rotundafolia, Ludwigia repens, Anacharis narrowleaf, Moneywort, Rotala Indica
- Floating Plants – Duckweed or Amazon frogbit
You do not need to get all the plants but even having one or two plants from each category can be a good idea. Most of these plants can be found in your local fish store.
Additionally, other owners of aquariums might also have plants to sell. These can be available at a lower price.
Add the Substrate Materials
Once you have all the plants, filtered the topsoil and washed the sand or gravel, it is time to assemble your tank. You will need at least 1 to 1.5-inches of topsoil in your tank.
If you’re creating a sloping effect, you will need to have 1 inch of topsoil in the front which gradually goes up to 1.5-inch topsoil in the back.
After this, you should add 1 inch of gravel or sand on top of the soil layer. Add enough to cover the soil but make sure not to smother it completely.
The soil needs to be slightly oxygenated. However, if you add too little, the topsoil will start to leech into the water when you fill the tank.
Watering the Substrate
Now you should add some water to the substrate.
Add only about 3 inches of conditioned and treated water into the tank. Try not to disturb the soil as much as possible.
Additionally, use a small twig and gently stir the sand to work out any extra air bubbles. This will ensure that the soil doesn’t leech out.
Introducing the Plants
Before you add the plants, make sure to go over the aquascape and layout design.
This will make the tank more aesthetically pleasing and ensure that any larger leafed plants are not blocking the view. Placing them to the back is a good idea.
Furthermore, you can keep the stem plants in the middle and the front of the aquarium.
Then, if you’re adding some rocks and driftwoods, tie the moss and the rhizome plants to them. Rhizome plants cannot be buried in the substrate as once the rhizome area gets under the soil, it will rot.
Once you have decided the layout, use some plant tweezers to firmly plant the roots inside the substrate. Make sure that they are deep enough to not get uprooted once you add water.
Filling the Tank
After you have fixed all the plants and are happy with the aquascape, you can fill the tank completely with water.
Fill it slowly, doing your best not to disturb the substrate and soil as much as possible. When you fill the tank up, it might loosen some plants. Just use your plant tweezers to add them back into the soil.
Moreover, expect the water to be cloudy or have bits of debris.
You can remove the debris but wait overnight to see how the water clears up. If the water is still cloudy, make sure that the sand or gravel layer is not leeching any soil. This can also introduce tannins which will make the water darker.
If the water doesn’t clear up after 48 hours, do a water change and then see what the issue is. Sometimes, you might need to add some more sand. To do this, you will have to remove all the water and then add the sand or gravel to the soil again.
Adding the Invertebrates
When the water has been cleared completely, it is time to put in the invertebrates that you picked out. Adding in the Amano shrimp and nitrite snails at this stage is a good idea.
They will help to kick-start the nitrogen cycle, aerate the soil, and break down excess waste.
Remember that Amano shrimp do need a food source. While they can eat algae, they will need algae wafers, shrimp food, and other pellets. Feed them as needed to ensure that they don’t get neglected at this stage.
Doing a Fishless Cycle
Now that you have all the components ready, you are going to do a fishless-cycle of the tank. This means that the nitrogen cycle will be established without the use of any fish. The Amano shrimp and the snail are going to the main source of ammonia in the water.
You will have to wait for at least 12 hours to see if the nitrogen cycle has been established. If it hasn’t started, add some fish food as a source of ammonia. Once the cycle starts, you will have to do a 25% water change every three days.
Test the water parameters frequently to ensure that the cycle is still functional. Your readings should show ammonia at 0ppm, nitrate at 0ppm and nitrites that are under 40ppm. Once you get these readings, you can introduce your fish into the aquarium.
Remember that this is a long process and it may take you around 3 to 4 weeks to get the cycle started before you can introduce the fish into the aquarium.
Adding In Your Betta Buddy
Once the water parameters show that the nitrogen cycle is established, it is time to add some fish to the tank.
To do so, add a water heater to bring the temperature up to 78oF to 80oF (25.5oC to 26.5oC). Then, you have to acclimate your Betta fish to the water temperature for half an hour. If you want to reduce the stress completely, try drip acclimating your Betta to ensure that it is not stressed out by the water.
And there you have it. Your self-sustaining aquarium for a Betta fish is ready.
The best part is that this kind of aquarium setup is perfect for almost any kind of fish that has to be kept alone.
Also read: Do Betta Fish Get Lonely?
You will have to maintain the tank every now and then to ensure that it is in perfect order. The following are a few things to look out for:
- Trimming plants as they grow – some can become too overgrown
- Adjust light requirements – too much light can encourage algae growth
- Test water parameters – an imbalance in ammonia, nitrates or nitrites can disrupt the nitrogen cycle
- Replace light bulbs – this has to be done every 9 to 12 months
- Water changes – once a month, do a 25% water change
- Top-off the water – Water evaporates from the top so be sure to add some more
With the help of these tips, you can have a fully-functional self-sustaining aquarium for your Betta fish that is extremely low maintenance.
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