Please, follow our recommendations to enjoy our boulders: 

  • Most of our boulders come completely clean. Even though, we recommend rinsing boulders with water before use to remove any remaining dust.

  • You can easily test if a boulder is inert or if it will change slightly the pH and hardness. Simply place few drops of vinegar on the rock. If the vinegar (a base substance) fizzes or foams, it indicates that the gravel contains some calcium.

  • Boulders that contain calcium may alter the pH and kH. This can be especially pronounced if you have acidic water or CO2 addition. You can easily control it by regular water changes with osmotic or soft water. You can also use a water softener.




Natural river boulders create a truly natural rolling stone riverbed impression. Elderly boulders have rich textures, stripes and have a cold colour pallet that will make any scape stunningly attractive and natural. You can play with the positioning of the different sizes to create depth in your aquarium.

Elderly boulders are the perfect match for elderly gravel size mix. You will also get stunning contrast by using Heaven sand.

Available in Mix sizes

*This is a highly sought after and extremely rare stone, supply is limited.

*This rock may raise pH and hardness slightly.

*Standard regular water changes is enough to keep the hardness under control.





Stunning vibrant pitch-black colour boulders, this rock fascinates for its smooth black-glazed surface, design possibilities are endless due to its excellent colour contrast and maze-like texture.  Black Venom Stone is a high-impact rock that magnifies the green of plants and moss. It is an ideal stone to create Iwagumi and as a complementing stone for ryoboku layouts.

Mix and match with Black Venom Nano Boulders and Heaven sand to achieve a high impact composition. 

Available in Mix size

*This rock may slightly rise water hardness.

*Standard regular water changes is enough to keep the hardness under control.

*An ideal stone for Iwagumi layouts.





The natural yellowish ochre boulder brings warmth to the nature scape. This boulder has beautiful smooth textures with rich warm palette tones that bring a new impression to the aquascaping world. You can create a perfectly harmonious scape by combining it with Bumbeblee gravels and one of those sands: Bumblebee sand, El Dorado sand or Tigris sand.

Available in Mix sizes

*Does not affect water hardness. 





An outstanding colourful boulder that creates a unique riverbed impression. The boulders range in color from dark red to maroon, and from green to blue and black. 


Lake McDonald is Glacier National Park's biggest lake in Montana, USA. One of the most striking features of this lake is the presence of a variety of coloured rocks and pebbles just below the water surface and on the shores. 

The coloured stones of lake McDonald are entirely the credit of the planet. The colour of the pebbles is due to the iron content in sedimentary pebble rocks and the degree of its oxidation. So, for example, where iron was in close contact with air, red colours prevail there. But green colours are typical for stones formed at great depths, where oxygen is very limited.

Initially, rocks were formed for millions of years and, depending on conditions, acquired those very amazing colours. Subsequently, these lake rocks were ground into small coloured pebbles by giant ice blocks during the Ice Age. Streams of meltwater brought coloured stones into the valley, which was filled with glacial runoffs.


Available in Mix sizes

*Does not affect water hardness.