I tried looking this product up but without success, I got two different spellings, and not the manufacturer's site for data. So, given what other members have said, I would not use this sand in a soft water fish species tank. It may be OK in a tank of fish requiring harder water. Any substrate that changes pH should be avoided unless the change is necessary.
The chemical properties of any sand, just as with gravel and rock, depends upon the natural rock from which the sand/gravel is derived. Calcareous rock (limestone, marble, dolomite, aragonite, coral, shells--latter are not rock obviously but often used in some aquarium gravels and sands) will continue to very slowly dissolve mineral into the water, increasing GH (general or total hardness) and pH. Not all fish do well in such conditions. Soft water species may have considerable difficulty, depending upon the initial GH and pH of the source water. Betta and cory were mentioned, and both are soft water species.