I believe it's just kalk (which is a good thing). Read the thread about the "homemade kalk" or the one on "dowflake" You're usually gonna drip (add) kalkwasser (kalk dissolved in water) or use a buffer.

There ain't no all in one product.

It wouldn't be such a bad thing to use your Red Sea jar and see what it does for you and then find you can get the same stuff much cheaper.
I bought some recently just to get some kalk and was highly disappointed because I didn't realize they included a FREE calcium test, which I didn't need and took up a good portion of the jar.

Or you could use a 2 part buffer (which you can also do much cheaper).

I've gone back and forth, but the two-part was actually what finally got my calcium levels up.

BTW, be careful not to add this too quickly to your tank. A little bit could through the small tank off for a wild ride.