I believe salt build up occurs when your soils ph is low so there is a nute block and the roots cannot take in the nutes required. I may be wrong but thats what I have learned here.
Bukdatass- Yeah I have been doing that for awhile now. I flushed with 3gal of water to try and clear up the build up. I was going to flush in 2 more days with a mild nuted ph water as a last flush as a last try to correct the build up.
Also, I just added a 150w hps on the side to help fluff out the buddage more during its last weeks.