CG420,
Sounds like things are going well. Tim1987 is a coco grower and buys cheap coco...then rinses it himself. He used warm water initially to help all the salt dissolve. Try that.
The phrase salts is a generic chemistry word...but when I refer to salt in coco I mean NaCl (table salt) or more accurately ocean salt.
There are also nutrient salts given off as by product of plant metabolism. Different thing completely and if you're watering to excess (20% runoff) that shouldn't be an issue. And I wouldn't worry about the stuff on outside of bag. Better there then in rootzone, Heh?
Cheers,
JD