I use Fox Farm, exclusively, these days, I never had that happen (except for a small amount of 'salting', around the cap threads) ... but, I would suggest, it probably either got old, or the cap may have been left off ? ... dunno, but it isn't common, that I know of ... I'd add a tiny bit of water, if it looks thick, and just shake the livin' crap outta it ! ... if it doesn't seem to dissolve thoroughly, I'd get a new bottle ... good luck :smokin: