You might search for some of my older posts about this, plus I just posted something on another current topic on this forum. I know alot about calcium reactors, I just don't feel like typing it out all over again. FWIW, I'm working on an article for a new section of our website on calcium reactor function, design, and use.

You have the flow backwards; enter at the bottom and exit the top. You can still internally circulate top to bottom.