2 in 1 cheap kalkstirrer and RO top up

Tobes

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Hi Guys, I've been thinking whether this idea will work.
In Pic A there is a RO reservoir with pump 1, pumping RO water through the kalkstirrer to the return chamber of the sump when the level is low. A float switch activates it. Now on the kalkstirrer there is a circulation pump 2 swirling the kalkwasser every now and then to mix it with the RO - depending on the settings of the timer.
If you put the RO top up pump 1 on a pedestal like in Pic B (this is to allow the kalkwasser powder to settle at the bottom without covering the pump) and add another powerhead pump 2 which does the same job as the circulation pump on the kalkstirrer - mixing the powder according to timer settings - so, when the float switch activates pump 1, it will still pump kalkwasser to the return chamber like the first setup. The only difference is a kalkstirrer costs R1250 - R1500 where with the second pic you only need a extra powerhead which might be R100 - R300.
What do you guys think?
There is probably another way of doing this somewhere on the forum :p
 
looks good, it should work cant see why not
 
That looks lekka Tobes.Let's wait for the Guru's as I've never used a kalkstirrer

As far as I know you don't need a kalkstirrer if you have a calcium reactor. A kalkstirrer keeps the alkalinity and pH constant ;)
 
Hi Tobes,

i am also trying to figure out the best way to dose kalkwasser in my system.... There is a thread called "kalkwasser in depth" which is a great thread on this very topic..... from what i have read there and in other places, my concern with pic b is that the slurry / powder would get into pump 1 when pump 2 stirrs the kalkwasser, it seems that this would reduce pump 11's life to something like a month or two???

The option i am considering is mixing up a concentration of kalkwasser (only the clear water, not using the slurry) and adding that to the RO water chamber. the degredation of the pump according to the literature should be much less ..... and again according to this article, the need for kalkwasser top up systems to be a sealed unit is greatly over rated. If one has a kalkwasser mix that is not saturated in the RO top up chamber then precipitation over the week or so that water is added to the tank system is negligable. the disadvantage is of course that every time you add RO water to the RO chamber you will have to add Kalkwasser conc....

My concern now is the PH spikes that i understand will take place when adding kalkwasser ....

my 2c worth, maybe the guru's have some more insight ??
 
I ran a kalkstirrer in my previous tank and the pH never spiked. My pH in the day was 8.2 and 8 at night. The circulation pump in the closed loop system on the kalkstirrer is a normal Resun 1200lph connected externaly. I can't see a difference whether it's external or internal. It never gave any problems in the 8 months I had it. The only big difference between the 2 setups is in pic 1 you have one pump pumping plain RO and the other one pumping RO + kalkwasser. In pic 2, both pumps will pump both RO and kalkwasser.
 
As far as I know you don't need a kalkstirrer if you have a calcium reactor. A kalkstirrer keeps the alkalinity and pH constant ;)

You do, as the CaRx increases the Alk to insane levels
 
Yip that's right.Why not just dump slaked lime in your RO drum Tobes?

Becareful, rather make a kalk solution and only use the clear liquid solution and get rid of the precipitate. The precipitate, has caused huge problems in my tank.
 
You do, as the CaRx increases the Alk to insane levels

I saw a few tanks that has a reactor but not a stirrer - then they must dose in another manner?
 
Hi Tobes,

The option i am considering is mixing up a concentration of kalkwasser (only the clear water, not using the slurry) and adding that to the RO water chamber. the degredation of the pump according to the literature should be much less ..... and again according to this article, the need for kalkwasser top up systems to be a sealed unit is greatly over rated. If one has a kalkwasser mix that is not saturated in the RO top up chamber then precipitation over the week or so that water is added to the tank system is negligable. the disadvantage is of course that every time you add RO water to the RO chamber you will have to add Kalkwasser conc....

My concern now is the PH spikes that i understand will take place when adding kalkwasser ....

Your option is a good way to go. I run a similar setup and my RO top-up runs at 13 pH and this counters my CaRx's high alk.

Being introduced via top-up there is no huge spike as said before.
 
Becareful, rather make a kalk solution and only use the clear liquid solution and get rid of the precipitate. The precipitate, has caused huge problems in my tank.

Even with say a Reeftek kalkstirrer you still get the precipitate (thick white mix) being dripped in at some stages. The circulation pump can run according to the timer and the float switch activating the top up pump at the same time.
 
Even with say a Reeftek kalkstirrer you still get the precipitate (thick white mix) being dripped in at some stages. The circulation pump can run according to the timer and the float switch activating the top up pump at the same time.

Yeah but that precipitate is not good, I had it in my top-up unit due to dosing and soon as this starting entering the tank, my Montis went for a ball of ......

Got rid of the precipitate and problem sorted. Believe me that stuff is evil.
 
the cause of precipitate, is it not from the solution being saturated?
so the liquid should be fine
 
Just to clarify something here - the precipitation happens, because of the calcium binding to either Carbon Dioxide, causing Calcium Carbonate, or to Phosphate ions, causing Calcium Phosphate.....

These BOTH are insoluble compounds, which looks like white snow when formed.

The negative thing about this, is that you LOOSE QUITE a bit of calcium, AND you alkalinity USUALLY drops, because of the precipitation.....

But, other than that - there's no problems with precipitation.....

Just to name the fact - I have only ever seen this ONCE happen - in my small 1.2 metre tank - around 3 months after I started my first real reef tank (modern reef tank - around 4 years ago) ever....

Never again....

My calcium levels are always around 420 to 520.... my alkalinity is always around 10 to 14.....
 
So, do you think my plan can work Jacques? I can even put a partitian between the top up pump and the 'stirring' pump to minimise the white mix to be pumped into the tank - like a settler of some sorts... if it will be better.
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Pic A should work perfectly, many people are running their RO/kalk in this manner.
 
Pic A should work perfectly, many people are running their RO/kalk in this manner.

I know Viper, but I'm trying to get a cheaper alternative seeing that a kalkstirrer will probably cost R1500-R2000 by now. I paid R1450 a year ago for a Reeftek KR100 and that time it was the cheapest quote. My question is if pic B will work?
 
The only difference is a kalkstirrer costs R1250 - R1500 where with the second pic you only need a extra powerhead which might be R100 - R300.
What do you guys think?

Yes, it will work. One thing to kep in mind, though - the commercial kalkstirrers operate under pressure (well, a little bit of pressure...) and excludes all air from the system, thereby ensuring that there is no CO2 available to degrade the lime.

I don't think this is very serious, though. My system works much the same, except it does not have the circulating pump - just a 50 liter container with a float valve from the RO filter keeping it full of RO water, and a large dose of hidrated lime added every weekend...

Hennie
 
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