Constantly fighting to keep my Ca up

[gregzz4]

Have you checked your water with someone else's test kits/different brands of kits?
Wouldn't hurt to make sure your test results are accurate.

I've never dosed Kalk, so no help here. But I'm surprised to hear that your Ca is dropping when your Alk isn't, and that you can't keep your Ca up when your Alk is.
Maybe it's due to the amount you dose of Ca not being fully integrated/absorbed by your water when you test ???

Maybe wait a bit longer after you dose before you test your Ca.
I usually wait at least an hour, if I test after dosing at all.

Keep in mind that when you dose either Alk or Ca, they play off each other and may see-saw their levels when they mix.

Hope I explained myself correctly and accurately ...

Good luck.