yeah i dont understand why more people dont just use nsw. petco sells it in boxes if you want it...little expensive but worth it considering all the time it takes mixing 5 kinds of salt to get some kind of magic formula...
i buy it in bulk for .99 cents a gallon from atlantis aquarium. take my pick up, fill up 6 or 7 of those 5 gallon h20 containers, bring em home and store them. good for months. the petco nsw (catalina water) is good for over a year.
sooo easy to do changes, just heat and pour. i do 5 gallons a week (55g tank). thats 6-7 weeks of changes sitting in my closet. syphon out one 5 gallon bucket of debris and other crap. pour in new water from container...i use one of those digital heaters with readout, stick the heating probe right in the container, voila...plug and play.
i get good results using nsw. i think you can get just as good using mix too. i used to use reefcrystals and marinemix. marinemix = uber salt mix.