Product review (1 stars): Created a fogbank
I have a Hunter 31005 that came with a few of these tablets. I normally use charcoal-filtered water, and haven't noticed any white dust buildup, but thought I'd try it out for internal tank maintenance.

Whoops. The tablet dissolved almost instantly in my tiny tank, and after 30 minutes I started to notice a haze throughout my apartment, hanging in the air.

Don't do it. filter your water, clean your tank.