To add to JD's comment, make sure you are aware of your current levels. If your CH is high, you probably don't want to use Cal-hypo. You probably get your water from the Edwards Aquifer, so you know how hard your local water is already. Also, using cal-hypo means knowing what your CYA (stabilizer) level is so you are balancing the FC to the CYA as noted on the
FC/CYA Levels.
So technically yes, you can use it, but not if your CH is already elevated. If it is, stick to liquid chlorine. Hope that helps.