If you wish to propagate a large amount of seeds or cuttings hydroponically, try these Grodan Rockwool SBS Cubes.
Grodan Rockwool SBS Cubes are designed specifically for hydroponics propagation. They are an inert growing media that will require a mild nutrient solution applied as soon as your plant roots are visible.
These 40mm propagation cubes are supplied in a tray to hold and support them and they can be contained in this tray inside a large propagator until a good root system has become established. When ready you can transplant the cubes into a larger Rockwool grow block or directly into another hydroponics media like clay pebbles.
Pre-soak these SBS cubes in an acidic solution of 5.5-5.8 PH for 24 hours before use as they are slightly alkaline.