is that caribsea supernaturals a good alternative ?
If it is actual sand, yes. They have some much larger (too large) gravels shown for this name. And you want to avoid white.
Any other recommendations when I do swap the substrate ?
It can take all day to do this, I would suggest a spare tank, doesn't have to be large, but one you can put the filter and heater from the display tank in, along with floating plants and some lower decor for shelter. Then you don't have to worry. When I changed my 5-foot tank it took all day, and it was late in the afternoon so I waited until the next morning to move the fish back, much less stressful if they have a day ahead of them to get used to their new home. I changed all my 8 tanks to sand, and the Flourite disaster was two changes. A spare tank really does make life easier here.