My Second Generation DIY Kalk Reactor

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.

 

Very nice Darren! I have been looking myself for something to build a kalk stirrer out of.

 

I have a question. Once the tank is empty do you have to clean whatever old powder remains?
I've read that dosing Kalk with your ATO is a good idea, never really used it. Now that I'm trying to keep coral I'm doing some more research.

 

I feed this with RO/DI water through an aqualifter pump so there is really nothing that has to be done once it's set up other than dump a bunch of kalk in every once in a while. I don't like the idea of running your ATO through it because you can't control the dosage.

I really do love this as a nearly maintenance free way of upping calc and alk (and mag if you use Brightwell Kalk+2)

 

Great job Darren. Looks about right for your big tank.
What is your method for replenishing the kalkwasser? How do you know how much to add?

 

For replenishing the kalk I just dump a bunch in the mixing chamber. Basically you want to saturate the kalkwasser in the chamber. Excess kalk sits in the bottom. When new fresh water is pumped in, saturated water goes out and the remaining water now in the chamber is slightly below saturation. That's where the mixing pump comes in. It stirs everything up and saturates it again withe excess kalk.

As to how much fresh water I pump in, it's a matter of picking an amount, trying it out for a while and measuring calc+alk. If it's too low then I raise the amount of time the aqualifter pumps to get more solution into the sump. Too high then I drop it.

 

That makes sense Darren. This morning I had forgotten about the aqualifter and overflow and wondered if you were returning it to your sump with your MAG!
Your method for timing on the pump is probably what I would do as well.
This is a real interesting design. I've never seen one like it.

Has it been effective? What have your water tests shown since?

matt

 

Good thread RM. I have a question slightly off topic about kalk. Do you find that you have to supplement ca or alk? I find that from time to time I'm having to adjust. And never adding equal amounts of either one. I'm using the BRS 2 part.

 

OK, one word on this thing here........................




................................BRILLIANT!

 

I do actually. I find that alk just doesn't keep up in my system. From time to time I supplement - I've added alk booster to my make up water and that helps.