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Hydrofarm

GROW!T GMC40l - 4mm-16mm Clay Pebbles, Brown, (40 Liter Bag) - Made from 100% Natural Clay, Can be used for Drainage, Decoration, Aquaponics, Hydroponics and Other Gardening Essentials

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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, May 23
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Size: 40 Liter Bag


Pattern Name: Bag


Features

  • Extremely stable in both pH and EC
  • Made from 100% natural clay
  • Pre-washed to aid in stability
  • Drain freely and do not hold any excess water, providing good oxygen levels around the root
  • Will not float once fully wet

Description

GROW!T horticultural clay pebbles are made from 100% natural clay. They are clean, pH stable, and offer great aeration and drainage in hydroponics, especially in flood and drain, deep water culture, and drip feed systems. Due to their unique structure and ability to cover a large surface area, they offer the ideal environment to foster beneficial bacterial growth around the root zone, leading to naturally healthier plants.GROW!T Clay Pebbles can be used for:•Aeration of growing media - ideal to mix into coco coir or soil to aid aeration •Drainage - will hold water as well as offering great aeration properties and free draining •Decoration - looks great as a top dressing for pots and also helps to prevent evaporation •Hydroponics/hydroculture - used widely in hydroponic growing, they are ideal for flood and drain, deep water culture and drip feed systems •Aquaponics - are also ideal to be used in aquaponic systems

Brand: Hydrofarm


Style: Classic


Item Weight: 20 Pounds


UPC:


Global Trade Identification Number: 44


Brand Name: Hydrofarm


UPC: 638104013444


Global Trade Identification Number: 44


Unit Count: 40.0 Count


Model Number: GMC40L


Manufacturer Part Number: GMC40L


Manufacturer: PLANT!T


Manufacturer Warranty Description: Warranty.


Included Components: Clay Pebbles


Item Type Name: Clay Pebbles


Style Name: Classic


Item Weight: 20 Pounds


Volume: 40 Liters


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, May 23

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Good product
Size: 40 Liter Bag Pattern Name: Bag
Clean and works well
Reviewed in the United States on November 17, 2025 by Jesse Sartin
    • Good value for starting semi-hydro
Size: 40 Liter Bag Pattern Name: Bag
Starting my semi-hydro plant journey and bought these. They're not like the perfect orange-y colored balls that you see some people using. These are a regular brown color and are more irregularly shaped, but that's fine for me because I had read it's actually easier to situate your plant in the irregular-shaped leca instead of the perfect balls. For the most part these haven't sunk after soaking them in water (even after soaking for weeks), but I don't think that really matters as far as actually using these for planting because none of the plants I've moved to leca have died and it's been a couple months now. ... show more
Reviewed in the United States on April 21, 2025 by CC
    • The best leca product there is, basically an industry standard
Size: 10 liter Pattern Name: Bag
If you require these, you already know what you need them for. The build quality is excellent. They are simple to setup and easy to use. They do an outstanding job of storing and transporting your water & nutrients. These are the golden standard of leca. Absolutely highly recommended.
Reviewed in the United States on May 26, 2025 by Andy
    • Works as intended.
Size: 40 Liter Bag Pattern Name: Bag
I went through a 40lt bag last year. The product works as intended. It is dirty and needs several rounds of cleaning. I also noticed a higher ph I had to float it in a bucket with a bubbler for 3 days stirring and adding ph down until the solution around it stabilized to around ph 6.0-65 and held for over 12 hours. Slightly inconvenient but it works and is decently priced. I am purchasing it again. ... show more
Reviewed in the United States on January 28, 2026 by Децимато
    • Waterfall
Review Image by Michael Twitty
Review Image by Michael Twitty
Review Image by Michael Twitty
Hydrofarm clay balls to keep moisture in my snake terranium. A great component for making a waterfall
Reviewed in the United States on March 19, 2026 by Michael Twitty
    • Worked great in my 55gal flood and drain system
Size: 40 Liter Bag Pattern Name: Bag
Review Image by John
I bought these for my flood and drain set-up. You have to clean these very well as they have a lot of powder from production. As I was cleaning I was worried because they all floated. I made sure all of the water was out of my barrels and filled to the top with rock. I then flooded them and I was very happy because the weight of the pebbles where enough to keep from floating up and over the sides. There is also maybe an inch of dry rock at the top of my system to prevent the growth of alge. They are perfect for my halfbarrel flood and drain. Also if your interested took just about 6 to fill 2 half barrels. Its a lot of money but after digging out my $150 of rock that tested fine with vineger but then the ph started creeping up was not fun either. This pebble is so light and easy on the hands to work with and should withstand for so long I'm happy with the investment. ... show more
Reviewed in the United States on August 4, 2018 by John
    • Great product
Size: 40 Liter Bag Pattern Name: Bag
Great product
Reviewed in the United States on November 17, 2025 by gary
    • Solid budget option
Size: 40 Liter Bag Pattern Name: Bag
You get A LOT for what you pay, but I struggle with this brand because they float so easily. Makes it harder to thoroughly clean them, and also makes it hard to water the plants. I find I have to mix in another brand of leca that’s more compact and heavy in order to offset the floating. It’s a solid budget option. I’m still saving a bit by not having to buy as much of the expensive stuff, but not as much as I hoped. ... show more
Reviewed in the United States on December 13, 2025 by dreamer194

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