Both can be used again.

Both add CYA (stabilizer) when used.

Both tend to lower pH as well, ESPECIALLY Tri-chlor pucks.

If you need chlorine RIGHT NOW and can't get bleach, you've got the Di-Chlor powder.

I keep di-chlor powder for just those times when I want to raise CYA. I usually like CYA around 30, but as we get into the Dog Days (like this Steam Bath Week here in the NY/NJ/CT area) I like to raise the CYA to 40 or even 50. So I use the Di-Chlor for that.

Keep them dry and cool.