I'd avoid cotton balls. Rumor has it that fibreglass insulation can be soaked to correct pH and then used, but test it on bagseed first.
stinkyattic Reviewed by stinkyattic on . I need some hydroponic help... I have an aeroponic system, everything is set up and ready to go, i have my pots with grow rocks in them, problem is.. I dont have any rockwool cubes to put the newly sprouted seeds in, can I place the the seed and the little root directly into the grow rocks? or inside a cotton ball? can I use a spongue instead of rockwool? I dont have any of those little cubes, can I still do this without them? there must be some easy alternatives Rating: 5