Bentonite Pond Sealant

Fix any leak in your pond with sodium bentonite

Sodium bentonite is a natural pond sealant that seals leaks in any pond regardless of its state, whether the pond is old, new, dry, or has water and fish.
Bentonite is one of the most efficient yet low-cost methods to repair or line a new pond.
We supply high-quality bentonite for pond sealing at wholesale prices and nationwide delivery.

How does Bentonite leak sealer reduces the seepage?

Bentonite changes from a powder to a muddy gel when mixed with water. This gel fills the cracks and pores in the pond floor, creating a natural and very resistant barrier that will keep the water in the pond.


You can apply Bentonite Pond Sealant on dry or full ponds, even in ponds with plants and fishes.


When the pond is full or has some water, you can sprinkle Sodium Bentonite on the water. Bentonite will sink and deposit itself at the bottom of the water tank filling pores and cracks and sealing them within a couple of days.


If the pond is dry or building a new pond, the pond sealer can be applied as a pond liner, creating a very efficient, low-cost, and long-lasting seal.

Pond after sodium bentonite application.
Pond after pond sealant application.

Bentonite Pond Sealer Advantages

  1. Volcanic ash that is a 100% natural earth material that does not involve other chemicals or hazardous substances.
  2. It is naturally erosion resistant and lasts for an extended period, mainly if applied using a blanket or mixed method.
  3. Is environmentally safe, no toxic, and no chemicals or additives. Safe for fish, plants, stock, and swimming – Eco-Friendly.
  4. The pond sealer clay is applied with simple farming tools or construction equipment, mainly during the pond’s construction.
  5. Each batch of bentonite is lab-tested, assuring top quality product before shipping the product.
  6. We are a certified manufacturing plant ISO 9001 certification that warranties our process and the products that we offer.
  7. We are involved in the full process of our products. We extract the mineral directly from our mines to assess the mineral quality.
Bentonite pond sealer
Sodium Bentonite Powder

How much Bentonite pond sealant do I need?

To determine the pond sealer amount that a pond needs, we must know the pond’s area and the type of soil.


The soil’s porosity dictates the amount per square foot your pond needs. The higher the porosity of the ground, the more product is needed to seal the pond. 


To approximate the pond’s area, we multiply twice the deppest point of the pond and add the resulting number to the length (L). And we also add that same number to the width (W), and we multiply both results L + (Depth times two) x W + (Depth times two), and the resulting number will be our estimated pond area.

To facilitate the calculation of the amount of Bentonite you have to use, you can use our Bentonite & Pond Area Calculator.


For any specific soil conditions, or for more information on how to apply pond sealer bentonite, contact our experts at our contact page or call us directly at our free 1-800 number to free your worries.

Bentonite Calculator

Calculator - Blog Post Automatic
Type of Soil of your Pond *
Whould you like to get a quote?

Complete the form and we will send you a quote in the next 48 hrs

Do you need help fixing a pond?

If you are having problems sealing a pond, we have the best solution.

We provide full service to fix ponds and lakes. We’ll supply the necessary equipment, operators, and mineral to seal your pond and offer you a turn-key job.

Talk with our experts they will tell you how we can help you to fix your pond.

machinery preparing then pond for pond sealing application
machinery preparing then pond for pond sealing application

What our clients say about our services and our bentonite for pond sealing

Chris PedersenChris Pedersen ★★★★★ Working with Lonestar was a pleasure from the start to the finish of the project. Ricardo (Rick) came out to walk the area and discuss the best option, and provided a detailed estimate within a couple days of initial contact. Next was meeting Joseph and his crew that did the excavation and application of the Bentonite. The process moved really quickly considering the work involved, and the entire team was extremely personable and professional. Overall I was very pleased with the entire experience and would recommend Lonestar to any potential customer without hesitation.jake spruielljake spruiell ★★★★★ I called in with a question and was fortunate to speak with a gentleman named Rick. He was very helpful and it was evident that he has the experience to answer any question asked with respect to their products. He went above and beyond in helping me and had a tremendous amount of patience. If you're sealing a pond and need sodium bentonite... I suggest you call Rick.Thomas FathereeThomas Fatheree ★★★★★ Product, service and pricing were excellent! I bought a pallet of Bentonite from Diego at Lonestar GTC Minerals and highly recommend checking with them for prices and product when planning out a job. Thanks Diego!Debra CribbDebra Cribb ★★★★★ Ric was extremely helpful and arranged 90,000 lbs of product transported by polite and on time trucking. We undoubtedly would recommend Ric and his team for your project!Marc BoucherMarc Boucher ★★★★★ Rick & Art did a wonderful job on expanding our 1/4 acre pond to a 3/4 acre pond that did not hold water. They were very professional and lived up to their promises!Thank you!Gary RylanderGary Rylander ★★★★★ Very professional group to work with. Everyone communicates well with you as a client and with each other. They also took photos along with texting updates which was helpful for documentation.Would highly recommend them.amy storyamy story ★★★★★ Extremely professional and very easy to work with. They provided us with a great product in a very timely manner. I highly recommend working with lone star materials!Chad RuttenChad Rutten ★★★★★ Ricardo was great! From the time I started talking with him until the time that they were completed with the project was around a few weeks. Our pond was only about a quarter acre, but meeting timeliness and responsiveness in this day and age is hard to find and brings a lot of value to the customer. They did a great job getting everything cleaned up after they were completed with the project. Now we are just waiting for some rain so we can get our pond filled. If I ever need another pond to be sealed, or if I decide to increase the size of this pond, I will be calling these guys again. I would recommend them to anyone who need a pond sealed. Thanks, Ricardo, and thanks to your team!Hat CreekHat Creek ★★★★★ Lonestar did a FANTASTIC job on my pond sealing. The application of material was very deliberate and reshaping of the pond will add a lot of surface area. Would highly recommend them and will be using them on my next pond!!!Edward HerbertEdward Herbert ★★★★★ This is the 5th contractor to attempt to put a pond in for our ranch, we can't wait to see the final product. Rick and Alex were great very professional. They took care of everything they said they were going to take care of.js_loader

How to use bentonite clay for ponds

While there are three main primary techniques available for applying sodium bentonite pond sealant, there are several factors you need to consider before selecting a proper application method.
The pond’s current state, along with the depth and dimensions of the pond and the soil quality, is of paramount importance when deciding on the application of the sealer to the pond.

The Blanket Method for Sodium Bentonite

This method is by far the most effective and popular method for bentonite pond sealant application.

First, any debris such as dead vegetation, including roots, logs, moss, trees, rocks, and other undesirable material must be removed in this method.

In the second step, all surface gaps, holes, or crevices must be filled with a mixture of 1 part of bentonite and five parts of soil (depending on the ground and using the reference table below on our Helpful Tools & Recommendations section.

This method is to completely cover all holes and gaps that are found at the surface.

A layer of bentonite pond leak sealer will be applied in the next step, spreading it to create a nice evenly blanket along the entire surface.

Once the bentonite has been applied on top of the surface, it is required to till it in or disk it in, just about 3 ~ 4 inches into the ground and compact. (Remember: Prevent bentonite from going into deep, because the more profound the product is in the soil, the more the bentonite is diluted.)

After you have compacted the bentonite, and if possible, you can spray water, wet the treated ground, and compact again.

The pond is now ready to be filled with water. Care should be taken in maintaining smooth and steady water flow in the pond so that soil or bentonite layers are not disturbed.


The Mixed Blanket Method for Sodium Bentonite Pond Sealant

The goal of this method is to have a very soft and even pond bottom.

As mentioned in the previous method, the mixed blanket method also begins with cleaning up all debris at the bottom and along the entire bed and then fill the holes.

The crucial move in this approach is to till the surface-go deeper in the process between 3 and 4 inches.

The purpose is to make the surface smooth and consistent by dragging the soil all along the waterbed.

Then apply a layer of Bentonite-soil mixture accordingly with the recommended ratio of bentonite per sqft area, cover it with 4 inches of soil, and compact. The final layer must be thicker if your livestock is going to have access to the pond.

Tractor Working on Pond
Tractor working in a pond with Bentonite

The Sprinkle Method for Sodium Bentonite Pond Sealant on a pond with water

Do you want to minimize water leakage in your lagoon or pond? Do you want to avoid the drainage of a water tank?  Sodium bentonite sprinkle method of applying and treating your pond liner to plug water drains.


This application method is used when a pond cannot be drained, either because of its size or for some other reason. When leaks have isolated, this approach can also be used. The process is less successful than the two previous methods, as there is no removal of trees, roots, and vegetation from the pond. And this method is not as accurate when sprinkled above water (could be a hit and miss).

In all application methods, it is important to notice that it may take a few days for the seepage to stop entirely because this is the time bentonite takes to hydrate to its fullest capacity and form a solid lining at the bottom. However, it is critical to know this for superior results: the required amount of sodium bentonite per square foot must be applied based on your soil type.

Truck sprinkling sodium bentonite
Truck sprinkling sodium bentonite in a lake

Still, want to learn more?

You may have more questions about sodium bentonite application techniques and our pond sealer product. Being a leading supplier of sodium bentonite, Lonestar Minerals will always be eager to answer any questions.

Our proven expertise can provide you with the most practical and economical solutions.

We can be contacted through our contact page or via our main phone number. Call us today, and we will be pleased to provide you with a free quote, send you samples of our products, or answer any questions you might have.

Available Packaging Sizes

We can supply Bentonite Pond Sealer in different packing sizes to meet your needs.

Order it by the full truckload (FTL) on pallets, super sacks, bulk, pneumatic trailer, or less than a full truckload (LTL) and by the pallet or super sack.

Sodium Bentonite 5 gallon bucket

50 lbs
Sodium Bentonite Plastic Bucket



Packing Information: 50 lb plastic bucket
Weight: 50 lbs.
Dimensions: 5 Gallon Bucket
Buckets per Pallet: 30 buckets
Buckets per full truckload: 540 – 18 pallets

50 lbs and 100 lbs Bentonite Powder

50 lbs
Sodium Bentonite Bags



Packing Information: 50 lb bags
Weight:  50 lbs
Dimensions: 18″ x 14″ x 4″
Bags per Pallet: 50
Bags per Full Truck Load: 900 – 18 pallets

50 lbs and 100 lbs Bentonite Powder

100 lbs
Sodium Bentonite Bags



Packing Information: 100 lb bags
Weight: 100 lbs
Dimensions: 25″ x 18″ x 4″
Bags per Pallet: 25
Bags per Full Truck Load: 450

bentonite pond sealer sack

3000 lbs
Bentonite Super Sack



Packing Information: Super Sack (no pallet)
Weight: 3,000 lbs each
Dimensions: 48″ X 48″ X 63″
Full truckload weight: 45,000 lbs.
Bags per full truckload:  15

bentonite 100 lb bags

Full Truckload  of
100 Lbs Bags Pallet



Packing Information: 100 lbs bags
Weight: 2,500 lbs (25/100 lb bags)
Dimensions: 48″ X 48″ X 63″
Full truckload weight: 45,000 lbs (45/100 lb bags)
Pallets per full truckload: 18

bentonite pond sealer sack

Full Truckload of
3000 Lbs Super Sack



Packing Information: Super Sack (without pallet)
Weight: 3,000 lbs each
Dimensions: 48″ X 48″ X 63″
Full truckload weight: 45,000 lbs.
Bags per full truckload:  15

Helpful Tools & Recommendations

How much sodium bentonite I needed to seal a pond?

Below you will find a small reference table depending on the type of soil and based on a maximum 8 ft depth. If the pond is deeper, you’ll have to add more bentonite per square foot.
You can also visit our online Bentonite Calculator for a quick reference calculation.

Soil condition → Pond sealant amount per square foot
Rock or gravel → 3.0 to 3.5 lbs / sq ft
Clean Sand → 2.5 to 3.5 lbs /sq ft
Silty Sand → 2.0 to 2.5 lbs / sq ft
Sandy Silt 20% Clay Min → 1.5 to 2.0 lbs / sq ft
Clay Soil → 1.0 to 1.5 lbs / sq ft

How is the bentonite pond liner delivered?


We offer bentonite pond sealant by the full truckload, less than a truckload, by the pallet, bag, or by the ton.
We offer our products delivered at any of our warehouses. (Inventory always available). Our main warehouse is in Laredo, TX. We have a secondary warehouse in Wyoming, where sodium bentonite is mined. We also have warehouses in Eagle Pass and Bulverde, TX (11 miles north of San Antonio, TX.)
We can coordinate logistics delivery nationwide at a very competitive rate. We can ship directly from our Wyoming mines depending on your location and the logistics cost. We can coordinate delivery from LTL –  less than a full truckload order to an FTL full truckload order. Contact Us to get a landed price quote.
Our headquarters office is in San Antonio, TX.

What happens after the bentonite is delivered? How to unload your order, equipment needed and weight of the bentonite.


Please consider that you’ll need equipment to unload 3,000 lbs super sacks or 2,500 lbs pallet from a flatbed truck. These super sacks have straps on top to grab with your tractor, excavator, front loader, bobcat, or forklift. and you can unload from the eighteen-wheeler flatbed truck.
Most of the time, the super sacks do not have wooden pallets underneath; if you require pallets, please call and request on your order (cost per pallet will be added to your order).
All our super sacks come with a very efficient discharge valve. The location of the discharge valve is underneath the super sack, for effortless pouring. To efficiently release the pond sealant, you must pick up the bag and untie the valve to start pouring the liner on top of your soil.

Do you offer a pond repair service?


Yes! Besides offering bentonite clay for ponds we also provide a complete service to repair your pond. With our turnkey service, we supply the minerals, equipment, experience, and workforce to make sure your pond is fully repaired, from draining it to filling it again.
We also design and construct new ponds. If you have an idea in mind, get a quote with us.

What are the physical specifications of our different mesh size particles of our line of products?


We offer a particular milled clay product for pond sealer that is a mix mesh powder granular product from fine 200 mesh powder to a 40-mesh mix.
This pond sealer is by far the best product for this application.
If you were to use a granular bigger particle size chips, you would need twice or three times as much to perform as good. (Please see the picture of our product so you can have a better idea of our product) to give you an idea, if you hold our product in your hand, it will feel like you were holding beach sand.