Red Sea coral pro salt?
 

Made the switch from IO reef crystals to this and it recommends to mix for no more than 4 hrs. Had a bucket going for a day for a WC... Still safe? Anyone have experience with this product?

Wonder why the recommend no more than 4 hours?... I mean it's going to be in solution and mixing for longer then that in your tank:question:

yeah....had me scratchin my head too...but would like to make sure...and it also requires that you mix unheated. then bring up to heat. then use... within 4 hrs...

I had a conversation with aquavitro about salinity and they also told me not to heat water. I asked them if I should take the heater out of DT also then :).
To which I stumped them.

I would mix as usuall heater and pump. I keep fresh mix all the time

I have been mixing mine the day before forever and never had a problem, kinda got me wondering though....

I've been using this salt for over a year and love it. I just mix it the day before or that day WITH the heater going, and I've never seen any ill effects.

Have att'er man. I don't know why they are trying to make it more complicated that it really is...

I think few brands suggest not to use heater because of the calcium concentration. Higher calcium contrasted salts are exothermic and makes the water hot anyway and adding extra heater can cause cloudy water. Using heater after mixing shouldn't an issue and hence once the mixed water goes into the tank with heater, its no longer their concern :P