Kalkwasser Stirrer KS 1000 - Aqua Medic

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Kalkwasser Stirrer KS 1000 - Aqua Medic

90% Recommend this to a friend (18 of 20)

SKU: 204130

reg. $309.99

Special Price: $263.49

In Stock: 11
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Quick Overview

Why does BRS recommend this?

The Aquamedic Kalkwasser Reactor is a very unique stirrer.  Kalkwasser is one of the easiest methods to supplement calcium and alkalinity, and using a kalkwasser reactor makes it even easier.  The Aquamedic Kalk Reactor can handle very low flow as the stirrer mechanism is not driven by water pressure, or stand-alone mixing pump.  The electric motor keeps the mixing of kalkwasser very consistent with low flow top off pumps.


  • Foot Print: 6.5" x 6.5" x 18.25"

  • Media Chamber Dimensions: 4" x 15"

  • Volume: 0.8 Gallons

  • Hose Connections: 1/4" inlet x 1/2" outlet

  • Media Capacity 150 grams.


Full Details

Aqua Medic Kalkwasser Stirrers feature a bar that slowly spins continuously to keep the kalkwasser saturated at the right level. At slow flow rates it does not create the heavy kalk slurry common with competing brands. This simple feature eliminates much of the overdose risk.

Many of the other kalkwasser reactors available use a mixing pump to vigorously mix the kalkwasser at periodic junctions. This creates a highly-concentrated slurry of kalkwasser that cannot be dosed until it has settled out. To protect against this danger, these types of reactors require a complicated series of timers to control pump operation.


Items 1 to 12 of 20 total

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  • Great By TKERacer619 on 10/14/2017

    I've been using this reactor linger than 10 years and I originally got it used. Motor finally gave out after all this time. Aquamedic CS was great.

    If you buy a kalk stirrer that has a pump instead of a stirrer you will end up replacing impellers often. This reactor uses a stirrer.

    I recommend feeding this with a high quality peristaltic pump that feeds at a slow rate and combine that with a good set of float switches. You do not want to use a kalk reactor with a high volume ato pump. The risk of dumping a lot of kalkwasser into your tank is high.
  • Defective motor on day one By Richard on 8/31/2017

    The motor spun slowly and jittered when it was first plugged in. After 60 minutes the motor no longer spins. I will find out how good aquamedics customer service is. Not impressed with their quality control.

    In the manual, it states the motor will only last 1 year and should be replaced annually. Seems to be a weak link in this item. The motor is $50. For a $300 unit, I would expect it to have a motor that lasts longer than a year.
  • Does the job well. By Atoll on 10/3/2016

    Been running my new AM Kalk reactor for a few monthss now and experienced non of the issues some appear to have had. No leaks and right sized tubing. Only down side is whoever fitted the check valve fitted it the wrong way round which stopped my RO topup water going through it. The reactor cost considerable less than the similar Deltec one so represents GVFM. I would have given it 5 stars if they check valve had been fitted the right way round.
  • Works but poor quality control By Jim on 4/26/2016

    Like others I basically had to replace tubing. The feed line assembly (one with check valve) was cut too short and it leaked because it could not fully engage with the murlok fittings. Beyond that I had sufficient parts around to get it hooked up to my Tunze ATO feed line. Its been a while but pretty sure I had to replace the return hose as the one included didn't fit.

    Otherwise it works as advertised but it remains to be seen how long that hot running motor lasts. So far its near silent in operation. For the simplicity of this unit and the materials used its pretty well overpriced. Its a stretch to say its worth even $200 let alone its $300 plus price tag,
  • good stirrer By Bruce on 3/21/2016

    As others have stated the inlet line pre assembled is too short and will leak, the 1/2 line supplied for outlet will not fit onto hose barb. I fixed mine with items I had on hand, for the money what is supplied should work. only my second day but it seems to be working as stated, if not for the wrong size tubing supplied I would give it 5 stars
  • So far so good By Aqua medic kalk stirrer on 3/21/2016

    Inlet tube from top to bottom was too short and was not seated, 1/2 tubing was wrong size , was able to fix with items I had on hand. So far appears to be working but only up one day. If they had fixed it based on all the complaints it would be worth five stars and maybe the price, should be able to use as shipped for the money.
  • Leaky shoddy design By Bob on 5/30/2015

    Could not get the inlet connection assembled without leaks. Inserted the supplied soft vinyl tubing into the MurLok style quick connect. It leaked. Tried 1/4" polyprop tubing. Could not get it fully engaged. Thought the unit was defective. BRS of course promptly replaced it. Replacement had the same problem. The unit uses tubing on the side that is .010" smaller diameter than the standard. Finally got it engaged by putting some silicone o ring grease on the end of the tube. Then both of the quick connects on the side leaked. The pieces had been cut too short, and were not fully engaged.
    O-rings on the top and the outlet shipped dry with nothing said about greasing them. The meagre instructions recommend 2 coffee cups of Kalk shaken with water to charge the stirrer. I had to write to the manufacturer to find out that 2 coffee cups is 8 oz. of dry kalk powder. Unless you enjoy this kind of misadventure, I'd sincerely suggest a different unit.
  • Self inflicted issues By Frank on 1/31/2015

    Now that I have had this running for a while I love it. I was really tired of mixing a 5 gallon bucket every week, and all the mess that came with it. I have a 150 with a 25 gallon sump and a 30 gallon frag tank all plumbed together. I do a constant drip with a Drew’s Doser which drips a little over 5 gallons a week. When I set up the stirrer the first issue I ran into was it leaked at the fitting where the inlet fitting goes into the cylinder. The leak was where the push connect tubing goes into the fitting. After messing with it for a while I determined the hose was too short to reach between the fittings and fully engage. After replacing the hose with a slightly longer hose all was well. The second problem was I just could not get any flow through with the Drews doser. I soon discovered that was because on the usual problem. I didn’t follow directions. When I filled the cylinder I just added 2 cups of dry Kalk instead of mixing it with RO and pouring the slurry into the cylinder. Dry Kalk packs in the hollow inlet part of the stirring shaft and a Drews doser just can’t push it through. So follow directions and mix the Kalk into a slurry first then add it to the stirrer.
  • Great and easy to use By Vern on 3/16/2014

    I had a different kalk reactor and I just fought and fought to get it to work just right. after dealing with it for a year enough was enough. I got this stirrer and hook it up to my ATO and is controlled with my Apex and all i have to do is keep kalk power in it and i'm set no more wondering if its going to crash my tank. It awesome just wish i had this the first time around so i had more time with my tank and not the reactor all the time.
  • Great Stirrer By Justin on 11/17/2012

    I've had this Kalk reactor running on my tank for more than a year and a half. The only problem with it that I've had was the stirrer cracked where the screw attaches it to the motor at the top. I had to buy a new stirrer. Other than that it's been great.
  • Good product By paul on 7/19/2012

    I have had this product for about 2 years. I love having it and find it a great way to add Kalk to your tank. It works really well although it has jammed up a few times and I had to force the shaft to get it to start turning, also I have had it squeak from time to time for extended periods, not too loud. I am using it with a Tunze Osmolator and it does a great job. you have to be careful though. If you have a small water leak or if you start doing a water change before you unplug the Ozmolator it will put concentrated kalk into you tank really fast. A controller would probably negate that possibility. All and all I would recommend it.
  • Good product...a little pricey By Bob on 5/14/2012

    The product works as described and doses the kalk as needed with the top off system. It seems to be a little expensive for the materials used but it works.


Ask a question

Product Questions

what kind of pump do i need with these please and how does this compare to the two little fishes model for $64. thanks
Question by: VAL on Jan 26, 2014 7:29:00 AM
Hi Val,
The aquamedic units are contantly stirring and mixing the water to keep a fully saturated solution which is a much more consistent product. The TLF models just rely on your ATO pumps blasting the kalk with enough power to mix it as it goes through. You can basically use just about any normal top off pump with the Aquamedic.
Answer by: Bulk Reef Supply on Jan 26, 2014 7:29:00 AM
I dont use a auto top off pump Mine is hard plumbed to my sump with a float valve.

Will this work?
Question by: Sean Wenz on May 18, 2017 6:35:00 PM
This type of stirrer can work very well for these types of setups. Just be sure that your water can freely flow from the stirrer to the tank and the water does not have to go up against any pressure. This type of stirrer is not meant to function with any internal pressure and any resistance to the free outflow of water may cause the internal water level to rise, getting up into the motor area. The water should flow freely with gravity from the source, through the reactor, and out to the sump.

Have a great day!
Answer by: Zack (Admin) on May 18, 2017 9:46:00 PM