Kruger Meier Onyx Magma Stones Porous Aquarium Substrate 2 kg

Kruger Meier Onyx Magma Stones is a dark, porous volcanic rock for the aquarium bottom.

It works as a lower layer under gravel or sand or as a stand-alone substrate, especially in biotope, natural and hardscape aquariums.

The stones come in two grain sizes, 4–8 mm and 10–20 mm, both in 2 kg packs. The material is natural magmatic rock with no additives. The porous structure gives nitrifying bacteria a surface to colonise and supports biological filtration. The dark, rough surface contrasts with green plants and the colours of fish.

Some dust may remain on the stones after transport, so rinse them before use. Then lay them on the bottom as the lower layer or leave them as the top layer.