hydroton and plant buildup

[VickiC]

I think I remember this subject being addressed in past threads, but I can't recall positively. If so, I can't locate the posts so I can refresh my memory (once again my bad memory shows it's ugly face).

The plants that I have potted in S/H seem very healthy and obviously like S/H just fine, but the top layer of hydroton and plant surface of 2 or 3 of these has either a mineral or fertilizer buildup. (I can't locate my list of my water components, so I don't have that info to tell you.)

I'm concerned if this buildup is/could be harmful if left as is. ?? Do you think it would be good to unpot the plants (clean the pot, of course, although I understand algae is no problem at all...just ugly.) then afterwards gently remove the hydroton, and repot with fresh media?

By the way, I water weakly weekly with fert, but I rinse ea. with fresh water alone about once ea. month. That doesn't seem to remove this buildup at all.

I've included 2 pictures, but I couldn't get the shots as good as I would have liked. Hopefully you can see what you need to know, though.

I would appreciate any advice and/or comments any of you may have for me.
Vicki