Review on Cylinder Aerator Diffuser Aquarium Connector by Jaclyn King

These air stones were used in a hydroponic system. The description even says "the aerator diffuser is suitable for hydroponic systems." However after ONE MONTH of use I took them out to inspect and noticed that there was some fine sand on my hand. I rubbed the stone lightly and it began to disintegrate and wear away in my hands. Who knows what chemical is holding these air stones together and I'm afraid my entire crop is now contaminated. I will be sending samples to a lab for testing but they are definitely not suitable for hydroponic use.