[TheReverend]

Seems like it could be used more than once and the manufacturer websites says it's possible... but they say it should be steam sterilized? Has anyone done it?


https://growstone.com/the-data/faq/

Can Growstones be reused?
Yes. Growstones keep their structural integrity over time, so it can be reused multiple times. As with any other substrate, sterilization between crops is recommended. When available, steam sterilization is the ideal option. With steam, a cubic yard of moist GS-1 Hydro Stones reach 200 ⁰F in less than 20 minutes without the use of a blower. This temperature can be maintained for 15 – 20 minutes after steam is turned off. So one cubic yard (27 ft3, about 174 gallons) of Growstones can be completely sterilized and ready to be reused in 35 – 40 minutes.

[TheReverend]

Don't everybody reply all at once!

[Dankdude]

sounds about right, 200* -212*f is about right, although when I was sterilize tattoo equipment, I ran my autoclave to around 250* f. there are a few substrates that can be reused.
as long as it eliminates any salt build up you should be good.

But alas this is the soil forum.