I never had salt build up when I grew hydro, so I can't say from first hand experience. I only grew hydro three times but I really never experienced any problems. I used the General Hydro 3-part, but only really used the bloom and micro with "Lucas formula" (maybe something you should look up, it makes things really easy). One word of advice though, whenever you have a problem, flush immediately for abut a day, and replace the reservoir. What's cool about hydro is that whenever you do notice something go wrong, you can always just switch out the media (water & nutes) and correct it within hours.