[NepNut]

Thanks poweramp for the detailed explanation. So far, the coco chips and coco peat that I got locally is safe for use. I usually let it soak for a few weeks changing water every few days untill the water is clearer (less tannic acid).

Athene,
I managed to get coco chips here from one of the nursery in Sg. Petani. By looking at the packaging, it's seems to be packed by local company. I also tried coco chips that I brought from a nursery in Hatyai, very cheap and seems to be of better quality.