A couple years ago I posted this thread about making my own kalk reactor. It worked very well for three years in my last system. Then I moved and set up a new system. Unfortunately, during the move something cracked at one of the joints where the PVC pipe goes into the main chamber. I played around with it, trying to seal it, but was having a heck of a time locking it down. Finally I just said "screw it" and decided to build a new one. So in building my next reactor, I wanted to solve for the following issues on my first: - Clear PVC is exceedingly expensive. I didn't want to use it again. - PVC ports and circular tanks don't work so well together (the root of my leak in the existing one) - Even at 6" in diameter, the first reactor was a little small if I needed to get into it. - If I wanted to drain the thing I needed to heft the whole unit over to the sink and dump it. It was risky (as evidenced by the port cracked during the move. I looked long and hard for a tank to act as the main chamber. I simply could not find a cost-effective solution. Then I happened on this one. Here is a pic of one that I bought (I actually bought 3 - I'll post what I'm doing with the other two later) What I like about it: - At about $70, it's quite reasonably priced and it comes in smaller sizes for smaller systems. - The cone bottom is cool because the undissolved kalk will concentrate in the bottom, narrowing the area where you need to mix. - It has flat sides which makes bulkheads easy. - It has an 8" screw-on top. - The cone has a 1.25" npt opening - just screw in a PVC fitting and you're good. - It isn't clear, but you can see enough through it to discern when the kalk is low. - It has a very cool mounting mechanism (see below) There are six screw inserts that you can use to mount the tank to a wall, board, etc. I mounted them to a pair of 2"x8" then mounted it to the wall next to the sump. I drilled holes for bulkheads for the drain to the sump and the mixer. The pump pulls from the top and pumps into the bottom. To make sure the kalk gets stirred up enough, I put a little PVC gizmo in the bottom that routes the flow from the stirring pump back to the bottom. Here's the gizmo inside the tank. You can see the outputs shooting downward to the cone bottom. Unfortunately the 1" PVC I was using was way too big for the Mag 3 I was using as a stirring pump to really mix anything. So I broke it all down and replaced the Mag 3 with a Mag 5 I had lying around. I also capped the two 1" outlets and drilled a 1/4" hole in the caps to create jets. It works very well now. As for how it works, RO/DI water gets pumped into the tank via an Aqualifter pump set on a timer. That water displaces the saturated kalk water which overflows into the sump. To keep it saturated, the mixing pump periodically stirs everything up. Seems to be working well so far.