What's a good stirring schedule for a kalk reactor with a stirrer?

[cherubfish pair]

Kalkwasser will be fed to tank through ATO. I have no idea what it takes to keep the kalkwasser at saturation point inside the reactor. The frequency will be controlled through a programmed Apex outlet. Reactor is AquaMedic.

[cherubfish pair]

How about frequency? More than once an hour or less?

[bertoni]

I've never used a Kalk reactors, so I can't help. Maybe someone else will add some comment.

[Larz_1]

I have an AquaMedic KS1000 fed by my Tunze Osmolator .
I never turn off the stirrer, just plug it in and it stirs the kalk continuously.
Been running it that way for years with no problem.

[dartier]

I use a K1 and it stirs constantly. I don't see any reason to not have it stirring 100% of the time.

Dennis

[rwb500]

I use a K1 and it stirs constantly. I don't see any reason to not have it stirring 100% of the time.

Dennis

three reasons:

1. you don't want suspended, non dissolved kalk to go through the feed pump (causes wear), or get in the aquarium.
2. surface agitation causes kalk to lose its potency, if it is exposed to air.
3. noise/electricity/equipment wear may be an issue depending on what you use to stir.

[Sk8r]

I use a 32 gallon trash can, stir it once every 3 weeks. Period. I went through 3 80.00 stirrers before I tossed the 300.oo reactor as a piece of junk I woudn't sell to anybody and poured the stuff in a Rubbermaid Brute can with no stirrer but the addition of fresh water every few weeks. Works like a charm.

[Larz_1]

three reasons:

1. you don't want suspended, non dissolved kalk to go through the feed pump (causes wear), or get in the aquarium.
That shouldn't happen if your system is set up properly. The ATO pump/res is BEFORE the Kalk stirrer and only the clear solution is dosed into your sump. Unless there is a float/sensor failure that causes an overdose.
2. surface agitation causes kalk to lose its potency, if it is exposed to air.
The stir is very slow and there is no surface agitation to speak of inside the Kalk stirrer. Not a concern.
3. noise/electricity/equipment wear may be an issue depending on what you use to stir.
There is no noise from my Kalk stirrer at all-I've had to check that it was still running. If you are concerned about the miniscule electricity usage of the stirrer motor-then you may be in the wrong hobby. Seriously, it is next to NOTHING. Wear may be a valid concern, but in the 5 years I've run my stirrer continuously-I only had to replace the motor once. And that was mostly my fault because It got wet by accident (and still ran fine for several months before I had to replace it). The replacement motor was like $15. For 5 years-I'd say that's pretty good.

[AcroporAddict]

three reasons:

1. you don't want suspended, non dissolved kalk to go through the feed pump (causes wear), or get in the aquarium.
2. surface agitation causes kalk to lose its potency, if it is exposed to air.
3. noise/electricity/equipment wear may be an issue depending on what you use to stir.

The Aqua-Medic Kalk stirrer line is meant to be on and turning 24/7. It uses a stir bar turning at a very slow rpm. Suspended Kalk does not enter the tank, as new water enters the stirrer from the ATO at the bottom, and clear, saturated Kalk enters the sump out the top of the reactor.

The water/air interface in a non sealed reactor creates a thin film of CaCO3 on the surface, with minimal loss, and the film actually lessens further interaction of the Kalk and CO2 from room air. This is not a problem with sealed reactors, as there is no room sir in the Kalk reactor in the first place. IIRC, Aqua-Medic Kalk reactors are sealed, and Avast K1 and K2 are not sealed.

The Aqua-Medic line of Kalk stirrers are virtually silent. And electric motor replacement after several years use is normal with a stirrer running 24/7, and should be considered a normal wear item.

[tmz]

I prefer a still reservoir and a timed peristaltic dosing pump. Stir it once when I fill it;let it settle for 90 minutes and dose the clear limewater . It holds it's strength for several weeks. Very steady been using it for about 8 years.

Still reservoirs are simple and reliable but do take more space.



Agitation in a reactor depends on the type of stirring that's occuring ( rapid /slow and frequency) and whether the reactor is air tight or not.
The goal is to get clear lime water(free of precipitated impurities and undissolved calcium hydroxide) without introducing CO2 via agitation. Observing the effluent from the reactor for precipitants or undissolved kalk and testing it for strength should help you decide on the timing for stirring and settling for a specific reactor.

[dartier]

three reasons:

1. you don't want suspended, non dissolved kalk to go through the feed pump (causes wear), or get in the aquarium.
2. surface agitation causes kalk to lose its potency, if it is exposed to air.
3. noise/electricity/equipment wear may be an issue depending on what you use to stir.

It sounds like you are thinking of the pump driven kind rather than stirred. The mixing pump versions do have the issue of undissolved Kalk entering the water column if you do not allow them to settle, whereas the stirred style has a layer of undissolved kalk at the bottom of the reactor 100% of the time which the stir bar slowly agitates (stirs). Mine spins at about 2-3 RPM.

A thin film of carbonate forms on the top of the water in the reactor, but the slow rotation of the stir rod does not disturb it, so the effluent maintains its potency.

I feed my K1 with a peristaltic pump on a periodic timer (to guarantee how much is being added each day), and the addition of fresh RODI slowly dissolves more kalk. Nothing but clear kalk water exits the reactor.

Dennis

[rwb500]

It sounds like you are thinking of the pump driven kind rather than stirred.

yes, my post was filled with qualifiers, which subsequent posts seem to have ignored. for example, if i said that noise might be a problem, you don't have to post back and tell me that your stirrer is quiet. if i said that air exposure can be a problem, don't post back and explain that your reactor is sealed.

and yes, in my post i quoted the guy who said that he used a koralia to stir his mixer.

if none of those three reasons that i mentioned apply to your situation than stir all you want.

[cherubfish pair]

I have an AquaMedic KS1000 fed by my Tunze Osmolator .
I never turn off the stirrer, just plug it in and it stirs the kalk continuously.
Been running it that way for years with no problem.
I have the same reactor and want to use a Tunze osmo as well. Is the metering pump strong enough to pump through the check valve on the reactor or did you have to take the check valve off? I blew air from my mouth through the check valve to check it and it gave quite some resistance. What are your thoughts on this?

[Larz_1]

I have the same reactor and want to use a Tunze osmo as well. Is the metering pump strong enough to pump through the check valve on the reactor or did you have to take the check valve off? I blew air from my mouth through the check valve to check it and it gave quite some resistance. What are your thoughts on this?

No problem at all.

[dkeller_nc]

I have the same reactor and want to use a Tunze osmo as well. Is the metering pump strong enough to pump through the check valve on the reactor or did you have to take the check valve off? I blew air from my mouth through the check valve to check it and it gave quite some resistance. What are your thoughts on this?

I use precisely this set-up: Tunze osmolator and Aqua Medic kalk stirrer. Yes, the metering pump is strong enough to pump through the aquamedic's check valve. But you will find that the factory-set flow rate through the osmolator is far too high for the AM kalk stirrer. Presuming that you're using a high-quality calcium hydroxide that's a fine powder, the factory-set flowrate will completely fill the reactor with suspended, solid kalk, and this will get dosed to your tank as a slurry.

To drop the flowrate, you will have to open the case of the osmolator controller and back the flowrate off substantially with the adjustment screw on the PCB. I use the "nano" flowrate.

You may also find that it's necessary to allow the AM to stir for a few hours after refreshing the reactor with new kalk (which needs to be done once per week, btw) before connecting it to your ATO to allow the finer particles to aggregate so they don't get blown into your tank.

[sghera64]

I have DIY reactor with a chem lab stir plate. The reactor is a 4" acrylic tube that is about 3 feet tall. My system ATO adds about 2 to 3 gallons of water each day. My stir plate comes on for 2 minutes every hour.

I decided on that because the kalk powder gets mixed well within the water column in 2 minutes. So that assures me it is saturated. It takes about 15 minutes for the "dust to settle" after the stirring bar stops. So I am confident that the water column is saturated. My DIY ATO is a slow drip that is on most of the time. The way I see it the new RO/DI water is sort of pushing that Kalk water up through the reactor from the bottom to the top. So I'm an hour only the bottom few inches of the reactor is unsaturated in kalk. By stirring every hour for 2 minutes I am assured that all the water that exits is saturated.


Because of my design I need to be careful not not agitate constantly because the kalk caught between the bottom of the reactor and the stir bar grinds the bottom out of the reactor.

[cherubfish pair]

I use precisely this set-up: Tunze osmolator and Aqua Medic kalk stirrer. Yes, the metering pump is strong enough to pump through the aquamedic's check valve. But you will find that the factory-set flow rate through the osmolator is far too high for the AM kalk stirrer. Presuming that you're using a high-quality calcium hydroxide that's a fine powder, the factory-set flowrate will completely fill the reactor with suspended, solid kalk, and this will get dosed to your tank as a slurry.

To drop the flowrate, you will have to open the case of the osmolator controller and back the flowrate off substantially with the adjustment screw on the PCB. I use the "nano" flowrate.

You may also find that it's necessary to allow the AM to stir for a few hours after refreshing the reactor with new kalk (which needs to be done once per week, btw) before connecting it to your ATO to allow the finer particles to aggregate so they don't get blown into your tank.
What's the adjustment screw on the PCB?

[dkeller_nc]

PCB = printed circuit board. You have to take apart the osmolator controller case to access the screw.

With regards to your original question, I run the AM kalk reactor for 5 minutes on, 5 minutes off. I do that principally to save wear and tear on the kalk reactor motor, though it's rated to run continuously.

[BradR]

I've run the big aqua medic for years and agree with running it continuously. On off cycles can actually wear things out faster than steady state on

[dkeller_nc]

That's generally true of devices with switches (heaters being a great example), ac motors, and heating elements but not so much with permanent-magnet DC motors. The in-rush current on a permanent magnet DC motor like the one used for the AquaMedic is minimal compared to an AC motor, so there's not too much heating of the windings to break down the insulation.

And failure of mechanical wear components like the bearings are generally dependent on run-time hours, so running the unit at 1/2 duty cycle will in theory extend its lifetime considerably.

So if you wish to run the unit intermittently for power consumption/lifetime considerations, you should be OK. Having said that, the amp draw on these stirrers is very low compared to everything else in a typical reef tank.

[AcroporAddict]

The only stir bar type talk stirrers not supposed to run 24/7 (per the manufacturers) that I am aware of is the one by Reef Octopus.

I have a custom pump style one by I had built by GEO, and I run it for 5 seconds every hour. This frequency keeps the lake stirred, but doesn't run the talk slurry all the way up to the top of the reactor, given the chance with this type of reactor that the ATO could turn on independently of when the pump is on.