You're on top of it already! I use a non PH livestock soap to do the first cleaning since D/2 is so expensive. 95% of my work is pro bono. It's called Orvus and works great! https://www.amazon.com/Orvus-WA-Paste-Cleaner-120oz/dp/B00OBPDOUS/ref=sr\_1\_2?dchild=1&keywords=orvus&qid=1629560707&sr=8-2
Perfect. This good to have too. It lasts forever and it a little goes a long way. Also, it doesn't harm the stone:
I get my D2 from Bicknell Supply in North Georgia:
Leslie Turpin
(800) 241-7105