Aquarium Substrates, Calcium Reactor Media & Refugium Mud

Brightwell Aquatics KoraLagoon Substrat (Substrate)
A blend of high-purity aragonite particulate grades to simulate the natural substrate particle profile of tropical reef lagoons.
CaribSea Substrate
Highest quality aragonite sand for your marine aquarium. Many different grain sizes to choose from, also available as live sand.
CaribSea Calcium Reactor Media
A complete reactor media containing not only calcium and carbonate, but essential trace elements as well.
EcoSystem Aquarium Miracle Mud
Miracle Mud is a product of EcoSystem Aquarium® that has been carefully formulated to include all the essential trace elements, minerals, and components necessary to maintain a successful aquarium.
Freshwater Planted/Cichlid Substrates
Ideal substrate for freshwater aquariums with live plants. Helps grow healthy and vibrant freshwater plants.
Two Little Fishies ReBorn Coarse Aragonite Calcium Reactor Media
Reborn™ coarse aragonite media for calcium reactors, composed of fossil skeletons of reef building corals sustainably harvested from pristine sites in the Western Pacific.
Live Rock and Dry Rock
AquaMaxx Dry Reef Rock
AquaMaxx Dry Live Rock is available in multiple shapes, sizes, and styles to suit all your aquascaping needs. It is free from pesky algae and hitch-hikers because it is dry.
CaribSea Life Rock
The ultimate liverock alternative! Safe for all fish and inverts, is made from an aragonitic base material, requires no curing, and is infused with spored, live bacteria. Once placed in water, the dormant bacteria will come alive and begin to colonize.
CaribSea Rubble Zone
The sky’s the limit for uses of this clean, high quality aragonitic rubble. For saltwater, the Rubble Zone can be used for attaching coral frags, refugiums, biological media, reef tank substructure, cryptic zones, or even jawfish habitats.
CaribSea South Seas Aquascaping Base Rock
South Seas Lace Rock is a great new aquascaping rock—more structure than any other commonly available aquascaping rock and is much more porous. Perfect alternative to live rock or can provide a very attractive base for live rock.
Fiji Best Saltwater Aquarium Live Rock
Fiji’s Best Saltwater Aquarium Live Rock is handpicked high-quality live rock collected from marine environments in Fiji.
Substrate is often used for cosmetic reasons to create a natural-looking environment inside the aquarium. But in addition to cosmetics, aquarium substrate plays a vital role in biological filtration by providing surface area in which nitrifying bacteria can grow.

Larger grain sizes—often referred to as crushed coral—are frequently used in fish-only aquariums because they allow for easier removal of detritus by vacuuming the substrate. In the reef aquarium, finer grains—generally referred to as sand—are used since the substrate provides a larger surface area that does not need to be vacuumed.

CaribSea Arag-Alive substrate contains nitrifying bacteria that 'seeds' an aquarium to speed up the cycling process. For fine substrate, 90 pounds covers a cubic foot. For coarser grains, 70 pounds covers a cubic foot. If you need help deciding how much substrate you’ll need, don’t hesitate to contact us for advice.

Along with saltwater aquarium substrate, you’ll also find calcium reactor media, refugium mud and specialized gravel for freshwater planted aquariums in this section.