Crushed Tumbled Black Aquarium & Terrarium Stones NB Minerals 8–12 mm 5 kg

NB Minerals crushed tumbled black stones in 8–12 mm grain size are natural mineral gravel sold in a 5 kg bag, designed for use in aquariums, terrariums and paludariums. These small, rounded black stones provide a stable and inert substrate layer suitable for decorative ground cover, plant anchoring and support of biological filtration. The product requires rinsing before use to remove dust and fine particles.

Advantages

This natural crushed tumbled stone offers uniform 8–12 mm grains that create an even surface and consistent appearance. The dark black color enhances contrast with plants and aquatic life while hiding debris between maintenance cycles. Being mineral-based and inert, the stones do not alter water chemistry under normal conditions and are durable against abrasion and dissolution. The 5 kg packing allows for spot applications or use in smaller setups without excess waste.

Suitable for

• Freshwater aquariums as decorative substrate and layered base
• Terrariums and reptile enclosures for ground cover and humidity retention
• Paludariums and paludarium borders for a natural shore aesthetic
• Plant anchoring for aquarium plants and potted terrarium vegetation
• Support of biological filtration when used with bio-media and substrate layering

Key specifications

• Grain size: 8–12 mm
• Color: black (natural mineral finish)
• Form: crushed, tumbled, rounded particles
• Pack weight: 5 kg
• Material: natural mineral gravel, inert under normal aquarium conditions

How to use

Before adding to an aquarium or terrarium, place the stones in a sieve and rinse thoroughly under running water until the rinse water runs clear. For aquariums, add a 1–3 cm decorative top layer over an appropriate substrate or use as a complete substrate depending on plant and animal needs. In terrariums, distribute evenly to create a natural ground cover and mix with other substrates where required for drainage and moisture control. Avoid using chemical cleaners or detergents; handle with clean hands or gloves to prevent contamination.

Usage recommendations

Rinse stones well before use and perform water parameter checks after installation in aquariums. Use the stones together with suitable substrate layers and filtration to maintain water quality. For planted aquariums, consider adding nutrient-rich substrate beneath the stones to support root growth. Replace or clean stones periodically during maintenance to remove trapped debris.