The GRODAN rockwool starting block is mainly used for cuttings and fits into the starting block with a large hole (40x40mm). Grodan rock wool has a neutral pH value and should be soaked and rinsed with pH values around 5.5 to 6.0 (never below 5!) Before starting breeding.

Suitable for
Starting block 7.5×7.5×6.5cm large hole
Starting block 10x10x6.5cm hole

Small cube 40x40mm