Best Substrates For Betta Fish Tanks Compared & Reviewed 2024

Betta fish are native to the Mekong River basin in Southeast Asia, their natural habitats have silty, muddy bottoms, often covered with leaf litter. So having a substrate for their tank helps build their natural environment.

But not only that, It provides anchor points and nutrients (depending on the type) for plants and a surface area for beneficial bacteria to thrive.

When it comes to betta tanks, the most common used are sand, gravel, and aqua soil. None of these are wrong to use, but they do all have their pros and cons.

In this guide, I’ll help you understand why knowing the difference between inert and active substrates is vital and share with you my favorite substrates I’ve used in betta tanks.

Overview of Substrate Recommendations

Chris’s 10 gallon blackwater betta fish tank

The best substrate will depend on the type of look you want your betta tank to have.

If you’re looking for ease of use, and don’t plan on having a bunch of root feeding plants, I’d go with a coarse sand substrate like Caribsea Super Naturals Aquarium Sand. You never need to change it and I love how sand looks in tanks and actually use this in my current blackwater betta tank. And it has a bunch of plants in it.

Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan
Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan

Last update on 2024-03-27 / Commissions Earned / Images from Amazon Product Advertising API

Seachem Flourite is easily the best gravel substrate for betta tanks in my option. Its ability to absorb nutrients from the water column and feed plant roots is unmatched by sand and other inert substrates.

Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs
Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs

    Last update on 2024-03-27 / Commissions Earned / Images from Amazon Product Advertising API

    If you want a lush, densely planted tank with a lot of color, and different plant species, ADA Amazonia is going to produce the best results for your betta tank. Just as long as you cycle the tank right during the initial ammonia spike, you’ll experience fast plant growth with

    ADA Aqua Soil Amazonia Ver 2 (3L)
    ADA Aqua Soil Amazonia Ver 2 (3L)

      Last update on 2024-03-28 / Commissions Earned / Images from Amazon Product Advertising API

      Inert vs. Active Substrates for Betta Tanks

      When it comes to choosing substrates for betta tanks, you have two options: inert or active.

      Inert Substrates

      Betta fish resting under plant

      Inert substrates are sand, gravel, clay based, marbles, and can come in any color, shape, and size.

      I highly recommend inert substrate to beginners because of their versatility and the fact they don’t have any affect on your water chemistry.

      They also never need to be replaced. You can’t keep any heavy root feeding plants with inert substrate (unless you use root tabs), but you can easily keep column feeding stem plants, rhizomes and floating plants by dosing an all-in-one fertilizer.

      Even if further down your journey in keeping an aquarium you want to try some root feeding plants, you can always add some root tabs to your substrate.

      Setting up a tank with inert substrate is more straightforward. You can add all substrates, plants, and decor as you please. And can easily start the nitrogen cycle process with fish food in order to make the environment safe for your betta before adding.

      Grain size is what is important when it comes to inert substrate. For sand you want 1-3mm grain size and gravel you’d want no more than 5mm. This is going to ensure it stays oxygenated and allow any stem plants to anchor properly.

      Pro Tip: Always rinse your substrate thoroughly before putting it in your tank. Dust tends to accumulate inside the bag from being shipped. Unrinsed substrate can turn your tank into a cloudy mess for days. To avoid this, put the substrate in a clean 5 gallon bucket and run water through it with a garden hose until the water runs clear.

      Active Substrates

      Red betta fish swiming in planted fish tank

      Active substrates leech minerals into your tank and affect the water chemistry. Now, this can be good and bad. It depends.

      Bettas originate from waterways that are very soft and acidic. They can be acclimated to a wide variety of water conditions, but they do best in neutral to slightly acidic water.

      Avoid substrates like aragonite sand or crushed coral. These substrates will constantly leach calcium and carbonate into the water, raising the GH, KH and pH.

      You should also consider if an aqua soil would be right for you. Aqua soils can lower the pH, which can be beneficial for betta fish or if your tap water is hard. They’re also fantastic if you want a high-tech tank with CO2, and a lush carpeting plant.

      You do need to be patient with active substrates. When you first set up your tank, it’ll leech a lot of ammonia into your water column. This means you have to do daily water changes in the first week, every other day the second week, and then every few days until the nitrogen cycle is complete. Then you can add fish.

      You can avoid doing all these water changes with a dark start. Simply add in the hardscape and soil, set up the filter and let it run for 2-4 weeks. Once the tank is cycled and you have no ammonia or nitrites, you can add plants and fish.

      However, they can be expensive, require replacing after one to two years, and aren’t essential for growing all types of plants. We’ll discuss more below.

      What Plants Will Be In The Tank?

      I always encourage people to add live plants to a Betta tank. Bettas need hiding places and they love to take little naps on plant leaves.

      And live plants can help improve water quality by taking up excess nutrients produced by fish waste.

      But what type of plants are you going to use? You have root feeders and column  feeders. Root feeders get their nutrients from the soil (so require an aqua soil to grow best) whereas column feeders get their nutrients from the water.

      Plants like Java fern or anubias grow best attached to something like rocks or driftwood. They don’t care what kind of substrate you use. 

      The same goes for floating plants, they’ll never even touch the substrate.

      Many stem plants, like Brazilian pennywort or ludwigia, feed directly from the water column. They can be planted in the substrate to anchor them, but otherwise they’re not picky, so you can use whichever substrate you prefer. You just need to dose with an all-in-one liquid fertilizer.

      Heavy root feeders, like Amazon swords, will do best in aqua soil. Their roots will spread under the surface and draw nutrients up into the body of the plant

      Best Betta Fish Tank Substrates Reviewed

      1. Seachem Flourite (Best Gravel)

      Seachem Flourite is a baked clay gravel designed to help support a planted betta tank without changing water chemistry. This material has a superior ability to hold and absorb nutrients from liquid fertilizers and fish waste than typical gravel or sand.

      As the company states, this substrate is good for the life of the aquarium.  

      The biggest problem people have with this product comes from getting it set up in the aquarium. Flourite can really build up an impressive amount of dust inside the bag.

      Your best bet is to put half the bag in a 5 gallon (19 liter) bucket and rinse it. And rinse it. And then rinse it again. 

      That’s really not an exaggeration AT ALL!!

      It’s impossible to get the water to run clear when you’re rinsing this stuff. 

      You just want to knock off the worst of the dust before you put it in the tank. 

      Then, once it’s rinsed, you should fill the aquarium very carefully and very slowly so particles aren’t kicked up into the water.

      When I set up a tank with this substrate, I fill the tank with a hose that is just barely seeping water. 

      If you’re filling the tank with buckets, the first few buckets of water will need to be put in very, very carefully. 

      Maybe even consider starting out with something like a 40 oz cup so you can really control the flow until you get several inches of water in the tank. 

      If you don’t rinse the Flourite, and then very carefully add the water, your aquarium will look like it’s filled with mud, and it can take up to a week to clear up.

      Although Flourite can be a pain to get set up initially, it really is a great choice if you want root feeding plants. I’ve used it for several years in one of my 40 gallon (151 liter) tanks. You can vacuum it just like you do regular gravel.

      The plants in that tank are very happy and have grown really well over a very long time.

      Flourite is easy to push plants down into with forceps, but it’s also dense and heavy enough that it easily weighs down new plants.

      Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs
      Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs

        Last update on 2024-03-27 / Commissions Earned / Images from Amazon Product Advertising API

        2. ADA Amazonia (Best Aqua Soil)

        ADA Aquasoil is an excellent option if you want to keep a densely planted betta tank.

        The biggest downside is it will eventually become depleted. This substrate will lower the pH and soften the water in your tank, which is ideal for a betta tank. Especially if your tap water is alkaline.

        Like all aqua soils, ADA amazonia is designed to leak ammonia into your water column. This means you can’t do a fish-in cycle. You must perform a fishless cycle and ensure the nitrifying bacteria has enough time to establish itself in your tank before adding a betta.

        One common issue people have with aqua soils, is the initial nutrient dump can cause an imbalance and spike algae. A good way to avoid this is to dark start your betta tank.

        Set up the soil, hardscape, filter, and let it run for a few weeks in the dark. This is going to cycle your tank, but the lack of light means no algae growth. Once the tank is cycled you can add your plants and betta.

        If you want to experiment with loads of different plants, have strong colors, and fast growth, ada aqua soil is going to be your best option.

        ADA Aqua Soil Amazonia Ver 2 (3L)
        ADA Aqua Soil Amazonia Ver 2 (3L)

          Last update on 2024-03-28 / Commissions Earned / Images from Amazon Product Advertising API

          3. Caribsea Super Naturals Aquarium Sand (Best Sand)

          CaribSea Super Naturals is a great choice if you’d like to have sand. It comes in a variety of colors that can really give your betta tank a natural look. 

          Sand also provides a lot of surface area for beneficial bacteria. And the Super Naturals line of sands from CaribSea are all inert and will not affect your water chemistry.

          There are some downsides to sand. You have to be sure to stir the sand bed periodically or else you run the risk of pockets of hydrogen sulfide (H2S), a foul smelling and highly toxic gas, developing under the sand’s surface.

          Stirring the sand up with your hand, or something like a wooden kitchen spoon, can prevent these gas pockets from forming.

          It’s also trickier to clean sand than it is gravel. If you try to push the gravel vacuum down into the sand, you’ll end up sucking up a bunch of sand into your bucket.

          The trick is to wave around the gravel vac tube about an inch above the surface of the sand. This stirs up the fish poop and detritus so you can siphon it out with the vacuum but avoid sucking up actual sand.

          Also, san simply will not work with an undergravel filter. The sand will just fall through the slots and fill in the gap below the filter plate, making it useless. 

          Lastly, sometimes sand isn’t a great plant substrate. It doesn’t provide plants with any kind of nutrients since it’s totally inert. And sand can compact and hamper plant roots from spreading easily; this is another reason to make sure that you stir your sand bed.

          Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan
          Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan

          Last update on 2024-03-27 / Commissions Earned / Images from Amazon Product Advertising API

          4. Aqueon Plant and Shrimp Substrate (Gravel)

          This substrate is another baked clay product, but instead of being in the shape of rough chips, like Flourite, the pieces of clay are spherical. 

          Aqueon substrate is much lighter weight than Seachem Flourite. So, it can sometimes be hard to get plants to stay in the substrate at first.

          Worst-case scenario, you can place some rocks around the base of the plant to weigh it down until it gets established.

          These baked clay spheres don’t break down over time; according to the manufacturer, they’re good for the life of the aquarium. 

          Just like the Seachem Flourite, the clay will absorb nutrients from liquid fertilizers that plants can feed on through their roots.

          I’ve had this substrate in a 5 gallon (19 liter) shrimp tank. I’ve had great success with small cryptocorynes and dwarf hair grass in that tank.

          Sale
          Aqueon Plant and Shrimp Aquarium Substrate 5 Pounds,Brown
          Aqueon Plant and Shrimp Aquarium Substrate 5 Pounds,Brown

            Last update on 2024-03-28 / Commissions Earned / Images from Amazon Product Advertising API

            5. AquaNatural Gold Pearl Gravel Substrate for Aquariums (Gravel)

            Gravel is by and large the most common aquarium substrate and a great choice for a Betta tank. This AquaNatural gravel is a mix of small river pebbles meant to give your tank a natural look. 

            I like that this gravel is a mix of different colored stones. I think that makes it look more like an actual creek bed.

            Gravel does a fairly good job of anchoring rooted plants, but it doesn’t provide any kind of nutrients for heavy root feeders.

            Fish poop will work its way into the gravel, so you have to make sure that you push your gravel vacuum tube down until you hit the bottom of the tank to suck out the accumulated wastes.

            AquaNatural Gold Pearl 10lb Gravel Substrate for Aquariums, terrariums and vivariums, 2-4mm
            AquaNatural Gold Pearl 10lb Gravel Substrate for Aquariums, terrariums and vivariums, 2-4mm

              Last update on 2024-03-28 / Commissions Earned / Images from Amazon Product Advertising API

              Which Substrate to Go With?

              It’ll depend on the look you want to achieve and you need to be guided by the plants you want to keep in your betta tank.

              Ada amazonia is always going to be best if you want to achieve a lush densely planted tank for your betta with bright colors. However, a gravel like seachem flourite can be an excellent alternative if you aren’t as concerned about having root feeders and just want to keep some easy, low-maintenance plants in your betta tank.

              The same can be said for sand. I love how a sand substrate looks in a betta tank and my current blackwater betta tank is using sand. And it supports plenty of plant growth. You just need to dose with liquid fertilizer.

              You can even try mixing. You can have aqua soil in densely planted areas as well as sand in unplanted areas. You can really create beautiful betta aquascapes with this method.

              If you want to go the inert route, but are struggling with higher pH, try adding indian almond leaves to your tank. This doesn’t only create a more natural environment for your betta, but they leach tannins which’ll drop pH and also provide some health benefits.

              Preview Product
              Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs Seachem Flourite Black Clay Gravel - Stable Porous Natural Planted Aquarium Substrate 15.4 lbs
              ADA Aqua Soil Amazonia Ver 2 (3L) ADA Aqua Soil Amazonia Ver 2 (3L)
              AquaNatural Gold Pearl 10lb Gravel Substrate for Aquariums, terrariums and vivariums, 2-4mm AquaNatural Gold Pearl 10lb Gravel Substrate for Aquariums, terrariums and vivariums, 2-4mm
              Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan Carib Sea Super Naturals Aquarium Sand, 10 lbs., Tan
              Aqueon Plant and Shrimp Aquarium Substrate 5 Pounds,Brown Aqueon Plant and Shrimp Aquarium Substrate 5 Pounds,Brown

              Last update on 2024-03-28 / Commissions Earned / Images from Amazon Product Advertising API

              Christopher Adams
              Christopher Adams

              Hey there, my name is Christopher, and I've successfully ran freshwater aquariums for the past few decades. The mission of this site is to make it simple for anyone to run their own freshwater aquarium.

              15 Comments

              1. Actually the limit to the size of a Betta Fish Tank or Bowl is 2 gallons,they may not be happy with the size,but some people have to take risks.A lot of people recommend 5 gallons,but its fine for people to keep Betta Fish under 5 gallons.I just wanted to point out that sentence since it may have offended people and its not actually true

              2. I’m a complete Betta newbie! I’m setting up my tank and I put sand on the bottom, with gravel on top. But how do I clean it? Sand and gravel seem to have different cleaning methods.

                • Hey Michale, you can angle your siphon so you don’t disturb the surface. And your gravel should protect your sand from any debris working its way in. You can check out our article on cleaning a fish tank for more information: https://modestfish.com/how-to-clean-your-fish-tank/

                  P.s., sorry it took so long for out response. It seems we missed your comment before.

              3. I’m a beginner in wanting to care properly for a bettafish. I plan to purchase a male veiltail from petsmart (I would purchase one from a smalltime petshop, but alas the closest pet store is an hour away, and its petsmart :/) I am going to nab a 5 gallon aquafilter tank with a built in filter, and led light to mimic natural lighting. I’m also getting a thermometer, proper drops for the enviornment, a 30 watt heater, and bloodworms. I can hopefully find some good live plants, but I wanted to know if there are any specific type of live plants that could be potentially harmful to a veiltail? I’m goin to try the combo you suggested, but I’m worried about what specific plants to buy.

                • Hello Kaula, thank you for your comment. Okay, so generally, if you’re adding your standard aquarium plants like Java Fern, Amazon Sword, Anubias etc. you’ll be fine. When it comes to your Veiltail, you want to avoid all sharp objects and rough edges in your tank (commonly caused by fake not live plants), so stick to the classic aquarium plants and you’ll be fine.

                  Wish you all the best of luck! And feel free to contact us if you have any more questions, I’ll always reply as soon as I can.

                  Happy fish keeping.

              4. Do you use the products you list on here? Because I would like to know if the gravel listed can get the hydrogen sulfide pockets since it is described as having very tiny pebbles on Amazon.

                • Hello, Erin. Thank you for your comment, sorry for the late response, I have been on a break. Yes, I have used a number of these products over time. Yes, it is possible to have hydrogen sulfide pockets, however, with smaller pebbles, it’s less likely to happen. If you stay on top of water changes and siphon your gravel, your chances will be reduced further. But, in this hobby you’re creating your own microenvironment, which could be completely different from mine–even if we had all the same stuff!

              5. Probably a silly question but, I am just being introduced to planted tanks and such. My betta buddy is in a 10 gal, no filter, no heater, no artificial lighting – some live potted plants and he seems to be a happy, healthy fish. He is waiting on a transfer to his new 29 gal, and I am interested in setting up our first planted tank home. Will this be possible w out the filter, heater, and artificial lighting?

                • Hey Susie, thank you for your comment. Yes, it’s possible to run a tank using plants as filtration, there are many examples on youtube so I suggest you check them out. But, I’ll be honest, they’re not the easiest of things to run long-term so I wouldn’t personally recommend it to a beginner. And about the heater/lighting, if your room temperature keeps your tank water around 80F it should be fine but there are risks, and if your tank’s plants are still getting enough natural lighting to stay alive, it is possible. Overall, yes it’s possible, but in my opinion difficult to maintain.

              6. Hey, I’m looking into setting up a betta fish tank. This is my first time keeping a fish, so I’m trying to figure things out. I want to use sand as my substrate, but I was wondering how you would go about cleaning sand, and if you could use a siphon for a tank with sand as the substrate.

                • Hello, Haleigh, thank you for your comment. Yes, you can use a siphon with a sand substrate. You just need to do it at an angle 🙂

              7. Hi! I’m doing a planted ten gallon betta tank at the moment with just sand as a substrate (using root tabs) and I was wondering your thoughts on sea chem Flourite as a base, with rounded pebble gravel on top? I’d like to add many more plants and maybe even move him to a 20 gallon long. Currently I have a couple Anubias species, some java fern, amazon sword, and floating anacharis/Elodea.
                I’d like to add some micro swords and bacopa, would that be okay for him?
                Thanks so much!

                • Thank you for your comment, Noelle. I don’t see why these plants would cause any issues :). Wish you all the best

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