Q.coconut husk chip washery
Seeking advice for setting up a kitchen scale coconut husk chip (CHC) washery, including buffering for making it suitable for use in soilless potting mix.
My advice would be to look around in your kitchen to see what you can use; if you want to make a larger setup, or buy special materials, you alone know the size and budget you're looking for. The thing is to rinse and drain several times.
The addition of various chemicals to adjust pH or aid in cation exchange is optional - some people do, some don't. I would advise you try different approaches until you find the one that works the best for whatever you're trying to grow.
You'll want to do quite a bit of research on this subject. This article should get you started: https://www.gardeningknowhow.com/garden-how-to/mulch/using-coconut-coir-mulch.htm