Salt Problem?

I just started the flowering period 3 days ago at which time I switched nutrients to Ionic Bloom 3-2-6. I've now noticed what appears to be a buildup of salt on the grodan rocks and rockwool. Is this a concern? The plants themselves look better than ever, however I don't know if this is a problem that will continue to grow more serious and end up harming the plants in the future. I've been watering maybe 20-30 minutes a day or less, and the pH is ok according to my last check.

This is a problem, I'm having the same. My first plant just fell over cause the stem started to shrivel from the base up. But the real problem is, is that no one on here seems to say anything about it! I'm still trying to figure out what to do. I have a thread too that I just posted. Let me know if you find anything and I'll do the same.