Large DIY Kalkwasser Reactor

[Nanogeek815]

Hello All,
I am looking to switch to kalkwasser from 2 part. I have over 300g of water in the tank and found that I would currently need 1g of kalkwasser per day to maintain alk.

I am monitoring alk and ph with a trident and apex to verify all is well.

I plan to dose throughout the day to make small changes continuously.

Here is my plan...

My only real concern is that the mixing pump would be in the water. I havent seen any reason not to do this?

The mixing pump would only be on for 5 min every 6 hours.

Any thoughts? Thanks!

 

[Max_nano]

I believe having a pump in there will make it prone to getting build up in the pump which will require somewhat frequent maintenance. Have you considered using a magnetic stir bar? I believe the icecap kalk reactor uses a stir bar.

It looks like you may have an apex, you could use an outlet to turn the stir bar and base on as frequently as is necessary

 

[Nanogeek815]

I believe having a pump in there will make it prone to getting build up in the pump which will require somewhat frequent maintenance. Have you considered using a magnetic stir bar? I believe the icecap kalk reactor uses a stir bar.

It looks like you may have an apex, you could use an outlet to turn the stir bar and base on as frequently as is necessary

That's a good idea. I'll look and see if I can find one that's strong enough.

 

[Max_nano]

That's a good idea. I'll look and see if I can find one that's strong enough.

Let me know if you find one. I’m considering it too. I have GHL dosers which have a stir plate you can connect but I’m unsure how powerful they are and what not

 

[Breadman03]

That's a good idea. I'll look and see if I can find one that's strong enough.

Take a look at the Avast kalk stirrer. I’m happy with mine, but you might also find inspiration,

 

[Max_nano]

Take a look at the Avast kalk stirrer. I’m happy with mine, but you might also find inspiration,

I like that they have it stirring 24/7 (right?)

It seems like mixing at intervals could make the saturation inconsistent

 

[Breadman03]

I like that they have it stirring 24/7 (right?)

It seems like mixing at intervals could make the saturation inconsistent

Yes, 24/7. Mines been running for about a year now and shows no signs of wear, but I’m sure you could play with on/off time to reduce energy consumption and wear without impacting saturation. Perhaps multiple paddles to stir more quickly would help though the motor uses very little power.

 

[HuduVudu]

I have a Reef Octo stirrer. If you are doing kalkwasser using one of these with a dosing pump is IMO the only way to do it. It is way easier.

P.S. I used my Apex to control the stirrer using the OSC function. According to the instructions the stirrer was supposed to be on for 15mins every 2 hours. The Apex made this dead simple.

 

[vanpire]

I made my own magnetic stirrer with strong magnets and stir for 3 min every hour. The stirring is controlled with my apex. Works really well. I used the Avast stirrer but it didn't work well for me.

 

[Nanogeek815]

I will post an update once done, however I was able to pick up a fan motor and 3D printed a paddle. I am hoping to finish tomorrow to post an update.

 

[deplinger]

following- pls post photos! i am interested in making a kalk stirrer also.

 

[Chuk]

Hello All,
I am looking to switch to kalkwasser from 2 part. I have over 300g of water in the tank and found that I would currently need 1g of kalkwasser per day to maintain alk.

I am monitoring alk and ph with a trident and apex to verify all is well.

I plan to dose throughout the day to make small changes continuously.

Here is my plan...

My only real concern is that the mixing pump would be in the water. I havent seen any reason not to do this?

The mixing pump would only be on for 5 min every 6 hours.

Any thoughts? Thanks!

One caution with that design. The flow rates of the 2 metering pumps needs to be exactly identical. If it’s not you can overflow or worse either over pressure and bust the reactor or pull a vacuum and collapse it if the top is sealed.
It would be safer to have a gravity overflow unpressurized design if possible rather than pumping in and out.

Just something to think about.

 

[Nanogeek815]

One caution with that design. The flow rates of the 2 metering pumps needs to be exactly identical. If it’s not you can overflow or worse either over pressure and bust the reactor or pull a vacuum and collapse it if the top is sealed.
It would be safer to have a gravity overflow unpressurized design if possible rather than pumping in and out.

Just something to think about.

If it were perfectly sealed, I would agree. In which case, I would only need to pump water in and the equal amount would be forced out.

This design uses a 5g bucket and lid that does not have a perfect seal. As such, the pressure is not an issue. Though it is not as ideal as a sealed system, this solution is a $10-$15 option, as opposed to a $200 ideal option.

 

[Nanogeek815]

I 3D Printed a stiring paddle that fits the motor shaft.

The motor is a 115v fan motor.
I glued the airline connectors in and close the lid.

The total cost was about $10.

The downside is that the hole around the motor shaft, and the bucket itself, don't have perfect seals. Therefore air can get in and some of the CO2 will likely be absorbed while mixing. To minimize this, I am keeping the bucket as full as I can to maximize the kalwasser to air ratio.

 

[CoralFragZ]

Nice work!

 

[vanpire]

I would skip both the stirring paddle and mixing pump. Use a homemade magnetic stirrer. I did this and it works great.

Check out this video. Magnetic stirrers work well, cheap to make and are reliable.

 

[cryptodendrum]

I'm doing what you are now investigating doing, and have had great success with it for 15 years, except that I only use one dosing pump from the Kalkwasser reactor to the sump. Water level is maintained in the Kalkwasser reactor using a Toilet float valve.

It is neither 100% air sealed nor do I use a stirrer (Randy Holmes-Farley, if I am not mistaken, has commented why the use of non-air-sealed isn't such a big deal). I use an 2600lph Eheim pump, and I use some stiff curved vinyl tubing to direct the flow to the bottom of the salt bucket I use, so as not to disturb the crust on the surface of the water too much.

I drop in a kilogram of dry kalk every 3 months, and the pH in the reactor stays at or above pH 12 for about 2 months. After 2 months, it'll start to drop below to somewhere between 10-11, but that last month, I increase the time to mix the sludge at the bottom, from 2 mins to 4-5 minutes which pumps it back up to 12. By the end of month 3, I have to recharge with another kilo of Kalk.

What I have in my setup that I do not see in yours is:
1.) I use a lift bottle (recycled cola bottle & bottom cut off) in the Kalkwasser reactor with about 1-2 inches of the top of the bottle above the water line. This is in case my pump were to fire at the same time (accidents happen) as the dosing pump were running, it'll keep most of the sludge / undissolved kalk from getting sucked into the dosing tube
2.) A sediment bottle - a sealed glass cola bottle inbetween the reactor and the dosing pump as a final catch all of any floating sediments from the Kalk. Over about a year of dosing, it always has 2-3 inches of sediment in the bottom.

Once a year, I tear it all down and clean everything out. The buildup on my Eheim pump isn't really an issue at all, and usually my attention is to my float valve. Everything gets a good wash and scrubbing with vinegar water, slapped back together and we're good for another year.

I have my controller setup to spread out the approx 6 liters of dosing Kalk as TopUp every hour during the night for 12 hours, to help reduce pH drops at night. During the day, it switches over to RO for the rest of AutoTopUp.

FWIW, my total system volume is about twice as yours, so I can't totally rely on Kalkwasser, so I run a Baling Lite / Kalkwaser Hybrid setup. Kalkwasser takes care of the majority of my CA / Alk needs, but I fill the small gap left over with minor dosing of CA & ALK via Balling, plus my Mag demands.

 

[cryptodendrum]

Hello All,
I am looking to switch to kalkwasser from 2 part. I have over 300g of water in the tank and found that I would currently need 1g of kalkwasser per day to maintain alk.

I am monitoring alk and ph with a trident and apex to verify all is well.

I plan to dose throughout the day to make small changes continuously.

Here is my plan...

My only real concern is that the mixing pump would be in the water. I havent seen any reason not to do this?

The mixing pump would only be on for 5 min every 6 hours.

Any thoughts? Thanks!

Well, I just had the 3 month reminder it was time to recharge my Kalkwasser reactor, so I made some photos of you of my setup, which has remained unchanged for almost 15 years now; in fact, that's the same salt bucket I started this with, but the toilet valve has been replaced 2 or 3 times now. The larger blue tub is a safety measure incase the toilet valve ever fails, which has happened once. Toilet valve failures are slow and subtle tho, just like when they are mounted in toilets. As you can see, the actual valve mechanism is above the Kalkwasser water line and not exposed to actual Kalk. The one time I had a failure, the reactor slowly over-filled and I noticed there was a problem when I saw about 2 inches of standing water inside the blue tub. I plan on adding a water sensor tied to my aquarium controller, but have simply been lazy and haven't done this yet.

Despite using a riser bottle inside the reactor, and extracting pretty clear kalkwasser from the reactor, running a secondary sediment collection bottle outside the reactor still catches some precipitate before dosing into the sump. That precipitate in this bottle now is about a year's worth of caught precipitate. As you can see, a years worth isn't a lot, and the riser bottle does a pretty good job on its own, but I like my Kalkwasser super clear.

I usually clean the Reactor and Precipitate bottle every spring (when the weather is warmer, because who wants to get wet in the backyard when it's 0C outside?). While I'm busy cleaning the reactor itself, I'll run vinegar through the dosing tubes & pump for a few hours and that cleans the lines clear again. My 80 liter RO water barrel (not featured here) sits on top of a "Beer, Phyto & Fishfood" fridge in our Fishroom, well above my head, so there's plenty of pressure on the water hose running to the toilet valve.

I have to correct myself here from my above comment: I said I recharge the reactor with a kilogram of Kalk, but I was wrong - it's 1000ml of Kalk, which comes out to just above half a kilogram. Still, despite the "inefficiencies" of not being an air-tight Kalkwasser reactor, 3 months for 9 Euro's worth of Kalkwasser powder it does pretty good, and it offsets the costs associated with CA / Alk Baling Salts I'd normally have to use if I didn't use this hybrid setup (4 kilograms of CA Baling salts alone is about 39 euros).

I tune my hybrid setup to dose as much Kalkwasser as possible up to the max possible until pH is peaking at max safe levels 8.5+ daily, and then use Baling salts to top up CA and Alk values the rest of the way.

Hope that helps you in your plans and build considerations.

PS- the damage to the wall in the photos isn't from the Kalkwasser reactor, it was related to a failure last year of a home Heating Expansion tank that was wall mounted to the left of the Kalkwasser reactor. I relocated a new Expansion replacement tank elsewhere in the room but still have to repair the plaster on the wall.