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Kalk Stirrer Kit
Kalk Stirrer Kit
Kalk Stirrer Kit

Kalk Stirrer Kit

66 Reviews
$ 159.99

The new motor driven design of our stirrer silently and gently mixes your calcium hydroxide 24 hours a day. This ensures that you are always dosing the freshest possible kalkwasser to your system. Since the undissolved particles are always kept at the bottom and the clear liquid is always at the top, this is the safest available way to dose kalkwasser. Simple top load design reduces the amount of time spent adding kalk powder to the reactor, which can be refilled in less than 1 minute.

No more powerheads to clean or replace, no more large vats of lime water taking up valuable space next to your tank. Once you try our new line of stirrers you'll never look at kalkwasser the same again.

Note that our stirrers are non-pressurized chambers; water enters through a 1/4" John Guest fitting in the lid and gravity drains out into your sump through the 1/2" union barb fitting in the side. The lid is not fixed in place; it lifts off for quick and easy kalk powder refills.

 Technical Data K1 K2
Tank Rating 400 Gallons 800 Gallons
Output capacity 7 Gallons/day 14 Gallons/day
Footprint 5.5" x 5.5" 7" x 7"
Height 21" 21"
Power AC 120v 3w AC 120v 3w
Warranty 1 year 1 year


Click Here to Download the User Manual

Click Here to Download the Assembly Manual

Customer Reviews

4.9 Based on 66 Reviews
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Paul H.
United States United States

Great Product

I am very pleased with the performance of this product. I bought a 5.5 inch unit last year and decided to go with the larger size on my main system. It works very well and was simple to assemble.

Christopher Z.
United States United States

Easy weekend project

Great easy fun little project for any diy reef keeper. Same some money and have fun doing it

Larry L.
United States United States

Easy and fast assembly, works great

Easy to assemble just by following the video instructions, really fast to get it up and running.

Steve H.
United States United States

DIY Kalk Stirrer

The first thing I noticed when unpacking and evaluating the materials was there were two items slightly different from what is shown on the website. The first was the internal 1/2" elbow. This is really just cosmetic but it also had a ~1\16" hole drilled for a siphon break (which it needs) . The second item and of greater note was the motor housing/cover. This was the only item that caused me pause. This was made of clear plastic/acrylic that was apparently ground to give a frosted opaque appearance so the motor is not visible. This could have had a better finish in my opinion. All other materials were smooth and machine finished. The motor housing had fairly rough finish similar to 3D printed parts but also had small splinters of plastic exposed that you could feel and see. I had already decided to paint this so it wasn't a big deal to me. I didn't feel the need to go through trouble of sending it back or even contacting AVAST so I can't honestly say if they are all like this or I just got one that slipped through the QC process. After 3 coats of Fusion the surface was smooth. This may have also been because this is a DIY kit and the AVAST assembled stirrers may not have this. Overall the materials appeared to be of good quality. The machining of the tube and groove for the watertight connection was of good quality and probably wouldn't even need to be sanded before gluing. I watched the AVAST video one time before assembly and it is pretty straight forward. The one recommendation I would give before assembling is anyone who is not familiar with this glue or has not used it from a tube should use it on some scrap acrylic/PVC first. One thing that is not mentioned is a siphon break or check valve on the fill tube. The 1/2" fill elbow has a hole drilled as mentioned above. However, if the fill reservoir is below the stirrer and there is no check valve or hole in the fill tube (needs to be inside the tube above the outlet elbow) it can siphon kalk back into the ATO/RO reservoir. This is common knowledge and not a knock on AVAST at all. Many people will use a peristaltic pump and this won't be of as great a concern. Overall I am happy with the quality and transaction as a hole. I am happy that AVAST gives us the opportunity to do DIY projects and feel other companies could learn from this. This is my first purchase from AVAST, but I will be making other purchases in the future. Overall I would give this 4.75 stars out of five with a slight deduction for the motor housing finish.

John D.
United States United States

Kalk reactor

I really like this product as the self build allows me detailed knowledge of how it works, build instructions were good and knowing what comes apart and how it comes apart when maintenance is required is an advantage. Simple and it works. i look forward to my next purchase from Avast Marine.