rockm

"You can buy a simple ph measurement kit or even small electronic ph devices at most decent garden centres.

BTW, when searching for PH meaurement I realised that there are also moisture measurement devices available - does anyone use one of these?"

The problem is that some of these testing devices (depends on the type of pH tester--pH test strips might work, but they won't give you an overall reading of the soil mass, only spotty info) won't work with bonsai soil. The moisture meter, in particular, is a highly unreliable, sometimes dangerous, device when used for bonsai soil. Without knowing the tiny scientific details, I've found they don't work. From what I understand, Since moisture meters measure water between particles of soil and bonsai soil's "chunky" texture and subsequent large spaces between particles, the meters always read "too dry." It will read "waaaay too dry" a few seconds after you water. You can water your trees to death using this device. Avoid them.