Just trying to get some feedback on Coralife salt mix. I have been using this salt mix for a few years now without any problems but I have noticed in the past year the salt mix is leaving a brown film/sludge in my mixing container. My water is ro/di with regular filter changes so no issue there. I have also noticed this same film coating my aquarium glass and settling on the sand bed. I do bi-weekly water changes of 40 gal on a 120g tank. Parameters are good with no algae problems except for this film. Appreciate any input.


