What's the difference: Kalk Reactor / Kalk Dripper / Kalk Stirrer?

[fishbox]

I'm gonna start dosing pickling lime to help with my Alk/Ca. As I was researching DIY drippers, I ran into all kinds of builds for reactors and stirrers. So I'm trying to figure out what's what and which I should focus on building.

Thanks in advance.....

 

[takayan]

I'm gonna start dosing pickling lime to help with my Alk/Ca. As I was researching DIY drippers, I ran into all kinds of builds for reactors and stirrers. So I'm trying to figure out what's what and which I should focus on building.

Thanks in advance.....

My understanding is like below.

Kalk reactor: it is reactor with a pump. Most of reactor include stirrer mechanism.
Kalk dropper: this is gravitational dosing. Very simple dosing method.
Kalk steer: I never heard it, but it sounds like just stieering kalk.

 

[chipmunkofdoom2]

Calcium hydroxide has a maximum solubility of about 2 tsp/gallon. It doesn't matter if you put 5 cups of kalkwasser powder in one gallon of water, only 2 tsp will ever dissolve. The rest will settle at the bottom of the container. So, if you want to use kalkwasser in your ATO, which most people do, you have to mix up a new batch every so often as your old batch runs out. Drippers fall into this category: you mix up a solution of kalkwasser, presumably at saturation (2 tsp/gallon) and slowly drip it into your tank.

Kalk stirrers and reactors operate a little differently. You basically dump a whole bunch of calcium hydroxide in the reactor, fill it with water, and close it up. You feed your ATO water through the reactor. Stirrers/reactors then stir the solution every so often in a slow, controlled manner. The result is that the solution inside the reactor is always at maximum solubility because it is always being mixed. As your ATO pumps water into the kalk reactor/stirrer, the stirring or mixing action makes sure the new fresh water is quickly saturated with calcium hydroxide. The benefit of stirrers/reactors is that they're lower maintenance. Simply dump in a bunch of kalkwasser and hook up your ATO. You only really have to clean out the reactor periodically and refill it with more calcium hydroxide. This also has the side benefit of always making sure the saturation is at 100%. Because calcium hydroxide dosing is limited to how much water evaporates from your tank, by making sure the solution is always 100% saturated you're getting the most kalkwasser in your tank as possible.

It's important to note that a kalkwasser reactor/stirrer being sealed is critically important to how the device functions. When CO2 is dissolved into a calcium hydroxide solution, the hydroxides will combine with the CO2 to form carbonate and bicarbonate. The carbonate and bicarbonate will then join up with the calcium to form calcium carbonate, and precipitate out of solution. The result is that you have a container full of calcium carbonate, which will not redissolve. It is only by being sealed and keeping CO2 out of the reactor that kalkwasser reactors can properly function.

Here's a BRS TV episode on the topic of kalk stirrers.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, I prefer dosing limewater (the english word for a calcium hydroxide solution, kalkwasser is a german word) from a settled reservoir.

THe advantages are impurities can settle out better and the potency may be easier to control.

Disadvantage is space is needed somewhere for a reservoir.

 

[fishbox]

FWIW, I prefer dosing limewater (the english word for a calcium hydroxide solution, kalkwasser is a german word) from a settled reservoir.

THe advantages are impurities can settle out better and the potency may be easier to control.

Disadvantage is space is needed somewhere for a reservoir.

By "settled reservoir" do you mean the drip method where it is not stirred? It sounds like the easiest and cheapest way to dose "calcium hydroxide" lol. I'm trying to stay cheap because I only have a few corals in the tank and probably won't add too much more as I'm planning an upgrade in tank size. I can't add the calcium hydroxide to my top off reservoir because I use the same reservoir for my ATO and RODI storage at the moment. So I'm thinking a one gallon container above the sump to drip from. I still have to read Randy's article and watch the BRS video but is it necessary to match the drip rate to my evap rate? I'm not sure what my evap rate is but lets say that it's 2g daily. Is there any issues with me just using a 1g drip reservoir for the calcium hydroxide and let the other gallon come from my ATO?

 

[vic5hands]

I have a Kalkwasser stirrer hooked up to my ATO so it is added at top off

 

[chipmunkofdoom2]

By "settled reservoir" do you mean the drip method where it is not stirred? It sounds like the easiest and cheapest way to dose "calcium hydroxide" lol. I'm trying to stay cheap because I only have a few corals in the tank and probably won't add too much more as I'm planning an upgrade in tank size. I can't add the calcium hydroxide to my top off reservoir because I use the same reservoir for my ATO and RODI storage at the moment. So I'm thinking a one gallon container above the sump to drip from. I still have to read Randy's article and watch the BRS video but is it necessary to match the drip rate to my evap rate? I'm not sure what my evap rate is but lets say that it's 2g daily. Is there any issues with me just using a 1g drip reservoir for the calcium hydroxide and let the other gallon come from my ATO?

No, there is no issue doing this the way you describe.

If you know how much carbonate alkalinity your tank consumes, you can use a calculator like this one to try to determine about how much one gallon of lime water will raise your alkalinity in one day.

 

[Randy Holmes-Farley Verified Community Expert]

By "settled reservoir" do you mean the drip method where it is not stirred? It sounds like the easiest and cheapest way to dose "calcium hydroxide" lol. I'm trying to stay cheap because I only have a few corals in the tank and probably won't add too much more as I'm planning an upgrade in tank size. I can't add the calcium hydroxide to my top off reservoir because I use the same reservoir for my ATO and RODI storage at the moment. So I'm thinking a one gallon container above the sump to drip from. I still have to read Randy's article and watch the BRS video but is it necessary to match the drip rate to my evap rate? I'm not sure what my evap rate is but lets say that it's 2g daily. Is there any issues with me just using a 1g drip reservoir for the calcium hydroxide and let the other gallon come from my ATO?

I mean make up a batch by stirring it for an hour or so (maybe only a few minutes, maybe overnight), then stop stirring, let the residual solids settle out, then either use a dosing pump, and ATO pump, or a dripper like an IV bag or other method to slowly add it.

I typically made up 130 gallons at a time, but many people make up 5 gallon buckets or a Brute cans worth.

 

[thatmanMIKEson]

The biggest take away from that was giving impurities a chance to settle out.


"THe advantages are impurities can settle out better and the potency may be easier to control".