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CaribSea Eco-Complete Planted Aquarium Substrate - 20 lbs - Black Nutrient-Rich Gravel for Freshwater Planted Tanks - Promotes Healthy Plant Growth & Water Stability

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Color: Black


Size: 20 POUNDS


Features

  • Nutrient-Rich Substrate: CaribSea Eco-Complete Black Substrate is packed with essential nutrients to support healthy plant growth in freshwater planted tanks.
  • Ideal for Planted Tanks: Specially designed for aquatic plants, it promotes strong root development and vibrant growth, creating a healthy, thriving tank.
  • Improves Water Stability: Supports biological filtration, reducing nitrates and maintaining a balanced environment for both fish and plants.
  • Contains Trace Elements: Eco-Complete is enriched with essential trace elements, improving plant health and promoting tank stability.
  • No Fertilizer Needed: With a blend of natural minerals and nutrients, this substrate reduces the need for fertilizers, offering a low-maintenance solution for planted tanks.

Description

CaribSea Eco-Complete 20-Pound Planted Aquarium, Black

Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 18 x 12 x 2 inches; 20 Pounds


Item model number ‏ : ‎ 770


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ June 9, 2004


Manufacturer ‏ : ‎ CaribSea, Inc


Best Sellers Rank: #76,143 in Pet Supplies (See Top 100 in Pet Supplies) #688 in Aquarium Water Treatments


#688 in Aquarium Water Treatments:


Customer Reviews: 4.6 4.6 out of 5 stars (5,051)


Item Weight: 20 pounds


Department: Unisex-Adult


Manufacturer: CaribSea, Inc


Item model number: 770


Date First Available: June 9, 2004


Item Package Dimensions L x W x H: 16.5 x 10.1 x 3.1 inches


Item Dimensions LxWxH: 18 x 12 x 2 inches


Item Weight: 20 Pounds


Brand Name: Carib Sea


Target Audience Keyword: fish


Directions: Add substrate to aquarium, rinse if necessary, add water and aquatic life.


Warranty Description: No Warranty


Model Name: Eco-Planted Black 20lb


Color: Black


Size: 20 POUNDS


Material: Plastic


Age Range Description: All Life Stages


Number of Items: 1


Style: Classic


Included Components: Gravel


Specific Uses for Product: Aquarium Substrate


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: within 30 days

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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Top Amazon Reviews


  • Great product! Looks amazing and easy to plant with it.
Color: Black Size: 20 POUNDS
I love this product! Bought 4 bags and the color is consistent between them. There is a few off color pieces in the mix but not many and to me it wasn't a problem to just press them in and bury them. I have never used this. It comes with a tad bit of water in the bag. It claims that it has nutrients. I used it as a surface layer but under that I did dirt mixed with sand, followed by 1 inch of sand and about 3 inches of this stuff. It worked out well and now I have a very deep substrate. This is basically gravel but is not painted and I am sure my plants will love this. Very nice to look at. I didn't bother checking the PH since it is in a new tank and you really should wait a while before adding fish. I expected it to make the water decently cloudy but it didn't hardly change the water color at all. Maybe just a little bit. Nothing to worry about. And I did not rinse it at all. Much better than your standard gravel which for sure you need to rinse. I spent a lot of time searching for the right gravel and I am glad I bought this. Well packaged too. No leaks in the bag. It is kind of pricey though. That is why I used play sand under it and packed it down. It of course needed to be rinsed first. This product sets nicely on top of the sand under it and doesn't sink in much. You can easily save some money by just using this to cap off some sand. If you use lava rock under it then the heavier rocks will eventually work it's way to the surface so you probably don't want to do that. ... show more
Reviewed in the United States on May 29, 2025 by K W

  • nice, easy to plant in!
Color: Black Size: 18lb
Not so sure how it grows plants yet, but it was super easy to plant them in this stuff. just to let you know, it is just tiny crushed lava rocks, not soil. its inert substrate. its definitely a cheaper option, but you will have to use root tabs if you don't use a layer of aqua soil. it didn't cloud my water, which is nice, don't rinse it, because it comes with a liquid that's apparently full of beneficial bacteria. the color is nice, i got the black. you can get the 18lb for a 20 gallon long. i have about half an inch to an inch layer in the front and about 4 inches in some places near the back with left over. unless you want evenly 3 inches or something, 18 lb. should be enough. i will mention that i used a sand cap, and some of the sand has sifted through the gravel, but only time will tell how it holds up. ... show more
Reviewed in the United States on March 1, 2025 by Michelle Castleberry

  • Superb! Why would you rinse???
Color: Black Size: 20 POUNDS
I am new to planted tanks. This is my very first attempt. I had a goldfish (Gunsmoke) as a dorm pet in college and then some guppies. I recently got a betta (Rupert Pad Kee Mao) for my desk at work, but he will need a home in my home when I need to be out of the office for extended periods. So I started research to make him a vaca home that rules. I spotted CaribSea Eco-Complete 20-Pound Planted Aquarium, Black, just because I wanted black/natural substrate and started to read reviews. Honestly, they almost scared me away from this, but so happy I went with my gut. This stuff is amazing. Mind you I have a 5 gallon and it was daunting getting 20 lbs. of substrate. I worried that only using part would be a total mess. But guess what, it is fantastic. You are going to make a mess with any substrate, just head to your tub and work there. Placing into the tank it was NASTY! So nasty that I thought about all the reviews to rinse it, second guessing and extremely worried about double work. No worries though, seriously DO NOT RINSE this substrate and read the directions especially when adding to an established tank. My little tank was almost clear an hour after running the filter. By the next day the tank was crystal clear. Planting day (Red Cabomba, Water Sprite, Banana Plant, Bacopa and Java Moss) it was so clean (with a few floaties). Planting did kick up a bit, but not as much as I would have thought. It is now day four and the plants, even after all the stress I put them through, are thriving. I have not run chemistry on this tank yet, but will in a few days once it balances itself out (I don't want to freak myself into a tizzy looking at readings). I will probably get another tank (do not tell my husband) to use what is left. It looks fantastic, very natural with bits of rose and tan. I'll try to get back and update when Rupert moves into his penthouse in the next month. Update: It has been over a year and I still love this substrate. I did have a large die-off of plants due to being lazy and not caring for my plants as I should. But both Rupert (he never did return to my office) and an Anubias that was added after the original review was posted are thriving. The other plants (micro-sword, Bacopa and Wisteria) after the initial die-off are also doing really well Yeah, I have had a Petco Betta for over a year and he looks great swimming over CaribSea Eco-Complete 20-Pound Planted Aquarium, Black. ... show more
Reviewed in the United States on October 27, 2012 by Elaine Bell

  • I like this stuff
Color: Black Size: 20 POUNDS
I use about two inches of it beneath soil and a cap of sand and have experienced excellent plant growth with this setup. It’s an inert substrate so no nutrients like soil but over time it does absorb nutrients from the water column, which gets redistributed to plant roots as nutrients. Unlike other plants substrates, it doesn’t need to be replaced over time. It retains the ability to feed plants for years, which is a plus, imo. It’s packed in water with vital bacteria in it so it tends to cloud water during the first week or two. It’s a good idea to do several 50% water changes during this time to balance out your tank. After a few weeks, the cloudiness will clear Packaged arrived quickly and in good condition ... show more
Reviewed in the United States on December 16, 2024 by Anthony Carabello

  • Good substrate, no big problems with it
Color: Black Size: 20 POUNDS
I purchased this substrate from Amazon because I had heard good reviews about it from the YouTube fish tank community. I set it up in my 55 gallon aquarium with a DIY black background, and boy do the plants look stunning! The black really brings out the color in my fish and the green/red in my plants. It has a large amount of nutrients in it, and I suppose you could use the substrate alone without fertilizers or CO2. I just use a $9.00 250m bottle of Flourish, an aquatic plant fertilizer that I bought at Petsmart. It lasts for 2 years for the size of my aquarium, so it's a worthy investment. My only complaint about this product is that it is kind of misleading when it says that it has beneficial bacteria in it to cycle your tank. Please don't take it like it will instantly cycle your tank. It comes packed in water which is cycled, and smells very foul when you cut open the bag. ALSO, make sure that when you open the bag that you open it up over your aquarium or over a tub/outside, as it is almost like vacuumed sealed and it will splash. I made that mistake and it spilled all over my floor. No big deal, though. Anyway, you need to let your aquarium cycle completely just like you would with any other aquarium. The substrate itself consists of very small sand particles and small sized granules. The package says that the small particles sift down to the bottom of the tank naturally to allow for optimum root growth and CO2/Nutrient supply, which is mostly true. Some of the particles still are on the top layer of the substrate, but overall the statement is true. The bag also says that you do not need to wash this substrate before filling your aquarium up. I have found this to be completely true. Because it comes packed in water, there is really no residual dust on the granules. You may have a little cloudiness for 2 hours to a day depending on the amount of filtration/size of the tank, but it's again no big deal. Only 3 days after setting up my tank the water was crystal clear. Overall I would give this substrate a 4/5. Would buy again, but not at the normal price it is listed for (30 bucks). I'd buy it from my LFS which sells it for 17 per 20 lbs. ... show more
Reviewed in the United States on June 23, 2012 by ~Elliot

  • Good product
Color: Black Size: 20 POUNDS
Good looking gravel if you want all black. I have a bright blue betta that looks great with it. I don’t know if it said this anywhere, but there is a lot of liquid in the bag along with the gravel. I poured it into my tank without knowing that and the added liquid made planting my plants more difficult. It’s been a month now and it seems to be doing good. ... show more
Reviewed in the United States on November 4, 2025 by Chandler

  • Perfect for any aquarium
Color: Black Size: 20 POUNDS
I'm a do it yourself kind of guy. Over the last month I've tried three different substrates for my planted aqarium. Laterite, sand/soil(from stream near my home) and this Eco complete. I cut the bag open and dumped it into my already couple months old 55 gallon planted tank. It did not change my water color, shock my fish, cloud plant leaves with dust. It's been two weeks or so since I opened the bag. My plants are stronger and branching out at lead and root. The black Eco complete adds a nice dark natural look to the tank. It's perfect for better depth perception and viewing. My fish are all comfortable and mating again. This Eco complete has good bacteria in it. It's strong enough to start your tank off from scratch, same day setup or add to an existing setup and buffer it to its proper levels. Don't let it dry out! If you find one bag isn't enough but can't wait pile it all on one side or in pots or mix in to your existing substrate. This stuff added so much bounce to my tank I moved it into my living room. The plants and fish are doing great. Eco complete is the best planted substrate I've used. ... show more
Reviewed in the United States on May 23, 2013 by Elijah Durham

  • Carib Sea Eco Complete Planted Black Aquarium Substrate Is the answer to growing healthy plants Carib Sea Eco Complete Planted Black Aquarium Substrate Is the answer to growing healthy plants
Color: Black Size: 20 POUNDS
I have a 35 gal bowed fish tank that I’ve switched from artificial plants to real ones. I had normal gravel in the bottom of my tank and planted the plants in that. I used Fertilizer tabs to help boost the growing of the plants but it was great until I had to clean the gravel when I changed the water, then I noticed that I was sucking up the broken down fertilizer tabs, I knew I had to find a different substrate. Right before I ordered this brand, I had noticed my rug below the tank was soaking wet! Yep, my biggest fear of going on vacation. I checked everything, looking for the leak. It was from the seals along both sides in the front of the bow. I have a 95 gal tank and a 10 gal “sick tank” for new fish or sick ones. So it took most of the day to transfer fish and plants and remove gravel, clean out the inside of the tank and reseal it again. In the meantime I did a good amount of research on the best substrate for plants and Corydoras and Angels and live bearers. I came up with Carib Sea Eco Complete Planted Black Aquarium Substrate every time. So I ordered it while I waited for all the new silicone to cure and it was able to be put back together again. Our shipping was so fast that we still had to wait until we could put the tank back together again, but once we did, I wished that I ordered a second bag because some of the deeply rooted plants needed more substrate on top of them to hold them down. I made it work by dividing the plants into smaller ones and moving or removing the other decorations.. The plants grew so healthy and my Corydoras went crazy grazing along the bottom. What I was having trouble getting started, was growing up and producing very healthy rooting system! I will be ordering again! ... show more
Reviewed in the United States on January 3, 2020 Reviewed in the United States on January 3, 2020 by DAVID R. BOYER

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