[NepNut]

Hi Richard,
The simplest way to check whether the source of coir chip that you obtain have salt content, just test it with a hydrometer. You can get it from a pet store that sell marine fishes and accessories. Hydrometer is use to check the salinity of the water.

I have been using bags and bags of coir chips, so far no ill effect as the source of coir chips is clean of salt and mainly used for horticulture purposes.