<a href=showthread.php?s=&postid=10507704#post10507704 target=_blank>Originally posted</a> by c_stowers
I will have to disagree with Randy on this one (even though I highly respect his opinion). I've noticed that even RODI grows bacteria if left stored for >2 weeks. This is apparent from the biofilm that accumulates on the surface, but is most noticable on the sides of the container it is stored within. I have noticed the same thing in stored SW. Maybe this bacteria has no effect, but I doubt so. The bacteria must be growing on something, and thus depleting some of the constituents of synthetic sea salt. Also, bacteria condition their media, typically to very low Ph. Thus, as they grow, they will lower the pH of the saltwater by re-buffering it themselves.