Nature's Ocean Natural Coral Aquarium Base Rock, 40-lb box

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$85.99 Chewy Price
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About This Item

Details

  • 100% natural aragonite rock is great for decorating aquariums, conserving natural reefs, coral farming, culturing rocks and growing live coral.
  • Rapidly adapts to live environments and will not affect the cycling of your tank water so it’s easy to set up.
  • Acts as a naturally porous biological filter and is free of biofilm so it’s perfect for aquascaping.
  • Naturally porous surface helps grow denitrifying marine bacteria that help decrease nitrate levels.
  • Works for saltwater and freshwater aquariums and has been pre-soaked to prevent leeching so you don’t need to soak it before using.

Instructions

Learn More About Nature's Ocean From Our Team of Experts

Frequently bought together

Questions & Answers

13 Customer Questions

How many rocks?

Answer by Chewy • Mar 23, 2018
2 rocks ranging from 12-17 inches in length are included.

Can I add this rock to an already established Marine setup with fish and corals?

Answer by Chewy • Jul 29, 2018
The unique shape of these rocks make it easy to stack when growing live corals or adding to coral-based environments.

Is it possible to request smaller rocks to make decorating multiple small tanks easier? A 12in rock won't fit well in a 5-10 gallon tank.

Answer by Chewy • Aug 20, 2019
While there is no option to request smaller pieces at this time, other pet parents have reported being able to easily break the coral into smaller pieces using a hammer and screw driver or chisel.

How long can the rock be out of the water?

Answer by Chewy • Feb 21, 2018
The Coral rock comes as dead base rock but once applied to saltwater it can take up to 3 weeks for it to become live.
Reviews
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4.3
Rated 4.3 out of 5 stars
136 Ratings
Terms & Conditions

104 Customer Reviews

Rated 5 out of 5 stars
By llsword on Nov 22, 2025

Beautiful

I was really amazed at the great sizes they were. My aquarium is very large and they look fabulous.. I thought maybe they wouldn’t be as nice as they are, but was

I was really amazed at the great sizes they were. My aquarium is very large and they look fabulous.. I thought maybe they wouldn’t be as nice as they are, but was so excited I bought a second box. A wonderful addition to my tank. I am very happy! Thx Chewy, you never disappoint me. L. L. Sword

Rated 1 out of 5 stars
By Jeffrey on Oct 27, 2025

Came as 4 large

Not great, came in four very large pieces, not really usable unless you have a 400-gallon tank. Each piece was over 12 inches with no places for the fish to hide

Not great, came in four very large pieces, not really usable unless you have a 400-gallon tank. Each piece was over 12 inches with no places for the fish to hide. It was also packed terribly, and many parts arrived broken. Overall, not usable at all.

Rated 5 out of 5 stars
By Scott on Oct 7, 2025

Much better than I expected!

I got 4 large rocks and a bit of rubble the broke off during shipping. It's exactly the right amount for my 60 gallon, and I did the hardest rock as it's own island

I got 4 large rocks and a bit of rubble the broke off during shipping. It's exactly the right amount for my 60 gallon, and I did the hardest rock as it's own island and the others stacked into an arch. Great pore structure. Best price I find online factoring in shipping.

Rated 1 out of 5 stars
By Amy on Nov 1, 2025

2 massive rocks

Expected to be able to put together an aquascape but what I received was two massive rocks, can’t do much with that. Used a hammer and a chisel to break it up, but

Expected to be able to put together an aquascape but what I received was two massive rocks, can’t do much with that. Used a hammer and a chisel to break it up, but ended up with piles of dust.

Rated 5 out of 5 stars
By Koda on Aug 30, 2025

Real Reef Rocks

Don't listen to bad reviews these are Real Reef Rocks at nice sizes and shapes. The bad reviews are probably just those trying to get a free replacement or something

Don't listen to bad reviews these are Real Reef Rocks at nice sizes and shapes. The bad reviews are probably just those trying to get a free replacement or something and these are the least expensive on the market you won't be disappointed with the purchase that's for sure. Shoot might as well buy 2 or 3 boxes at a time just to get the bioload quota over and done with instead of waiting to add more later on so go on and do what feels right.

Rated 5 out of 5 stars
By Justin on Nov 14, 2025

Great value

As described, came on time, rocks were all larger chunks than I needed for a 20 gallon, but it is very easy to break up with a chisel and hammer

As described, came on time, rocks were all larger chunks than I needed for a 20 gallon, but it is very easy to break up with a chisel and hammer

Rated 5 out of 5 stars
By J on Oct 23, 2025

Just as expected

Great base rock, breaking up larger pieces with hammer/chisel. Exactly as expected. Each box was about a pound or 2 over.

Great base rock, breaking up larger pieces with hammer/chisel. Exactly as expected. Each box was about a pound or 2 over.

Rated 1 out of 5 stars
By eric on Jun 13, 2025

Two bass rocks no

I received four pieces maybe as a large as 9 inches not happy about that and on top of it they don’t look anything like the pictures. It looks like they were moved

I received four pieces maybe as a large as 9 inches not happy about that and on top of it they don’t look anything like the pictures. It looks like they were moved around by an excavator any little points that they had are rubbed off and it looks like a white scratched rock. But it looks like I’m the only unhappy person. I would’ve been happy with five rocks if they looked OK

Rated 5 out of 5 stars
By Roberto on Jun 1, 2025

Excellent selection and mix of rocks.

From some of the other comments I expected either two large rocks I’d have to break up or a bunch of rubble. But when I opened the box I was more than excited for

From some of the other comments I expected either two large rocks I’d have to break up or a bunch of rubble. But when I opened the box I was more than excited for the excellent selection I received. There were about 8-10 medium sized rocks with excellent shapes and almost all of them had one flat side so that they could sit level. I would definitely recommend.

Rated 2 out of 5 stars
By ALEX on Oct 16, 2025

Broken up.

The rocks came broken up. Only two of the three were intact.

The rocks came broken up. Only two of the three were intact.