Aqualexs Ohko Dragon Stone Rock Mixed Sizes (20 LBS) Review (2026)

Who this hardscape pack is for

Aqualexs Ohko Dragon Stone in mixed sizes at 20 pounds is aimed at aquascapers planning a hardscape-heavy layout in a medium to large tank, generally in the 25 to 55 gallon range based on typical recommendations for this weight of rock. Dragon stone's jagged, scaled texture and natural gray tone make it a common choice for naturalistic mountain or valley-style layouts, and the mixed sizing in this pack, generally covering a range of smaller pieces, gives enough variety to build a main focal stone along with secondary and accent pieces without needing to order multiple separate packs. It is less suited to a nano tank, where a smaller 5 or so pound pack of dragon stone offers a more appropriate scale.

What the rock actually is

Dragon stone, also called ohko stone, is a relatively hard, porous rock known for its jagged edges, sharp lines and natural gray color, which gives it the scaled, dragon-skin appearance the name references. It carries a neutral pH profile, meaning it should not significantly shift water hardness or pH the way limestone-based rocks can, and it is described as non-toxic to fish, shrimp and other aquatic life once cleaned. Its hardness and irregular shape make it good at anchoring moss or plants tied onto the rock face, and its stability under water helps stacked arrangements stay put once a layout is built, provided pieces are set on a level substrate base.

Setting it up and living with it

Before placing dragon stone in a tank, it needs a thorough scrub under running water to remove surface clay and loose debris left over from quarrying, since this dust can cloud the water and take days to settle if the rock goes in unwashed. Because the stone is porous, some aquascapers also soak pieces for a period before use to help release trapped sediment from inside the pores. Once installed, dragon stone generally needs little ongoing maintenance beyond normal algae control, since its texture can host some algae growth over time, which many aquascapers consider part of its natural, weathered look rather than a problem to solve.

Honest trade-offs and how it compares

The heavier a hardscape load gets, the more it matters that the tank sits on a sturdy, level stand, since 20 pounds of stacked rock concentrates weight unevenly compared with loose substrate, so check your stand's rated capacity before building a tall arrangement. Against a smaller 5 pound pack of the same Aqualexs dragon stone, this 20 pound mixed pack is the better value when a layout genuinely needs multiple pieces at different scales, while the smaller pack suits a nano tank or a single accent piece. Compared with seiryu stone, dragon stone is the pick when a warmer gray, rougher texture fits the intended scape better and when raising hardness is a concern, since dragon stone's neutral chemistry is gentler on soft water setups than seiryu's mild alkalinity.

Verdict and who should pick something else

This pack is a solid choice for a medium to large aquascape that needs a genuine range of rock sizes from one order, supporting our score of 8.6 out of 10 for value and variety. The mixed sizing does most of the work here, since it removes the guesswork of ordering several separate packs and hoping the pieces end up in proportion to each other once stacked. Choose a smaller pack instead for a nano tank or a single accent stone, and consider seiryu stone instead of dragon stone if the scape calls for a cooler, bluer gray tone rather than dragon stone's warmer, more textured look.

Frequently asked questions