Dosing Kalkwasser

cjr579

New member
I have a few question about dosing kalkwasser in my ATO. My ATO is a 8 gallon trash can. The RODI water automatically replenishes every day. When I dose kalk can I mix 1 gallon of RODI water and some kalk in a separate jug and just dump it right into my ATO? Is that the easiest way to do it or should I just put the kalk right into the ATO and have a powerhead mix it in the ATO container. IF i dump the 1 gallon of kalk premixed in the jug into my ATO which contains 5 gallons of rodi would that change the saturation of calcium hydroxide?

I'm I putting too much thought into this?


Thanks
 
You don't want the powder to get into the dt, you only want the saturated water to reach the dt. Also kalk does best in a seal container as air will weaken the kalk. Just my experience. Good luck!!!
 
You don't want the powder to get into the dt, you only want the saturated water to reach the dt. Also kalk does best in a seal container as air will weaken the kalk. Just my experience. Good luck!!!

What happens if the powder reaches the display? I top off manually and add a teaspoon or two to my ro/di jug every time I make water and it keeps my alk/cal stable, but I know some of the powder must be reaching the tank as I poor it in.
 
The main reason is that kalk have a high ph value and could and will over time raise your ph too high. I will try and find the article on it.
 
Calcium hydroxide( aka kalk/limewater) is best dosed clear without particulate matter. The particulates in it are undissolved calcium hydroxide and precipitated impurities. Any undissolved powder will dissolve in the tank and may cause a pH spike or may settle on coral tissue and burn it. The precipitated impurities may be harmful as well as they may dissolve when they hit the lower pH tank water.
Kalk should be dosed slowly in small increments,preferably over a 24 hour period . The maximum amount that will dissolve in fresh water is 2 tsps per gallon. At 2tsps per gallon .the pH of the solution is 12.4pH. To avoid pH spikes in the aquarium , no more than approximately 1/8th of a gallon of that solution should be dosed in any given hour per 50 gallons of aquarium water volume. Typically, that works out to a spread dose over at least 5 hours to meet daily top off needs. Letting it settle after stirring for an hour or two is also important. Exposing the solution to the air and stirring it will increase CO2 amounts entering the kalk water which will cause the solution to loose strength.
 
Some people say they use the balling method successfully to introduce Kalk? I think that means they use a small volume of water that is over saturated with Kalk and they pour into sump? Does this work? Does it introduce impurities? What are the pro and cons? How much of a rise in ph after a balling shot is acceptable? That is if ph goes from 8.1 to 8.4 quickly, is it damaging? Thanks for responding in advance!!!
 
The way I add mine is I will take a gallon of water, mix 1-2 tsp and shake it up to dissolve. I use Mrs Wages pickeling lime. Once the solution is settled, usually about 8 hours or so, I then put another lid on the jug that has a tube going down to about 1" from the bottom. That is usually where all the precipitate has settled. The lid also has a small tube that is still in the jug, just above the liquid level. Makes it easy to start a flow, just blow into the short tube and the liquid will go up the long tube near the bottom. The other end of the long tube is down in the sump near the water outlet of the skimmer. It has a flow valve on it so I adjust the flow to a drip and let it drip into the sump overnight. Has worked great for many years, but I now have a dosing pump, so I am going to try and set that up to dispense the liquid. Although I will still use the siphon method to get it into the dosing container so as to not get the precipitate.
 
When dosing Kalk is it possible/likely that the solution will clog the line usually at the exit point
 
Some people say they use the balling method successfully to introduce Kalk? I think that means they use a small volume of water that is over saturated with Kalk and they pour into sump? Does this work? Does it introduce impurities? What are the pro and cons? How much of a rise in ph after a balling shot is acceptable? That is if ph goes from 8.1 to 8.4 quickly, is it damaging? Thanks for responding in advance!!!

The balling method refers to calcium chloride and carbonate /bicarbonate additions, commonly called two part dosing. It does not relate to kalk dosing.

Dosing a slurry of kalk will introduce impurities,undissolved calcium hydroxide and spike pH which is undesireable .Steady parameters and slow dosing the clear limewater is safer.

This is from Randy H Falrely's article cited above: (note ignore the picture of the reactor ;it copied wit hteh quote and I can't seem to erase it).


"..4. Delivering a small amount of limewater all at once. Adding 1.25% of the aquarium’s volume (1.25 gallons of limewater per 100 gallons of aquarium water) as saturated limewater all at once raises the pH by 0.6 to 0.7 pH units. Such an increase is clearly too large. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 0.25% of the aquarium volume (0.25 gallons or 1 L of limewater per 100 gallons of aquarium water) will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable. The other concern with all-at-once dosing is that the local pH in the area of the addition will rise considerably higher than the values above. So dosing must be done far from living organisms, and in high flow areas that will facilitate fast mixture. In some aquaria, such restrictions make all-at-once dosing of limewater prohibitively risky to living organisms.
5. Delivering a small amount of solid lime slurried (dispersed) in a small amount of water. Adding one level teaspoon of solid lime (Ca(OH)2) slurried in a cup of water to 40 gallons of aquarium water all at once raises the pH by 0.6 to 0.7 pH units. That is clearly too much. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 1/4 teaspoon to 40 gallons will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable. The other concern with all at once dosing is that the local pH in the area of the addition will rise considerably higher than the values above. Moreover, dosing a slurry raises the added concern that the solids must dissolve before encountering organisms that may take them up and be harmed. So it is best to dose such materials to a sump, and watch that they completely dissolve before reaching the main aquarium or a refugium. In many aquaria, such restrictions make all–at-once dosing of a slurry prohibitively risky to living organisms..."
 
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When dosing Kalk is it possible/likely that the solution will clog the line usually at the exit point

I've been dosing it as clear limewater from a still reservoir via a timed peristaltic pump for about 8 or 9 years. The delivery tube sits out of the water about 6 to 10 inches inches over the surface of a high flow area in the sump. Clogging is extremly infrequent , partial clogting or calcium carbonate buildup is sometimes evident once every 2 months ,usually less frequent than that.It's partial ,never had it stop dosing. It is easily cleared and with a poke from an awl or ice pick.
 
So if I mix up 1 tbs kalk in a gallon container and pour the calcium hydroxide right into my 8 gallon ATO, will that change the concentration of Kalk or will it be ok?
 
So if I mix up 1 tbs kalk in a gallon container and pour the calcium hydroxide right into my 8 gallon ATO, will that change the concentration of Kalk or will it be ok?

If I understand your question correctly.......does that mean you will end up with 1tbs/9gallons? That's ok but a bit diluted? As mention you can do up to 2tbs/gal. Or 16 tbs for your 8 gal container at full. You can always use less if your demand is less
 
If I understand your question correctly.......does that mean you will end up with 1tbs/9gallons? That's ok but a bit diluted? As mention you can do up to 2tbs/gal. Or 16 tbs for your 8 gal container at full. You can always use less if your demand is less

Yes. I was thinking it would be a bit diluted. My ATO container usually has about 5 gallons in it. Guess I'll start by adding 1 gallon of calcium hydroxide to my ATO a few times a week and see where my calcium is at the end of the week and adjust accordingly.
 
So if I mix up 1 tbs kalk in a gallon container and pour the calcium hydroxide right into my 8 gallon ATO, will that change the concentration of Kalk or will it be ok?



2 TEASPOONS per gallon is the saturation level of lime in RODI water. If you put a tablespoon in a gallon and stir it won't go into solution and you'll pour undissolved lime into your 8 gallons where it will settle and be of no use.
 
Guess I'll start by adding 1 gallon of calcium hydroxide to my ATO a few times a week and see where my calcium is at the end of the week and adjust accordingly.

Add it once and then wait until your ATO is nearly empty. If you repeatedly add it you'll diminish it's effectiveness each time.
 
Wow, that's a lot of responses.

To start using an ATO reservoir with Kalk, I'd just add 1 tsp for each gallon of fresh water in the reservoir, and stir very briefly, maybe 4-5 seconds. Your tank might need more or less Kalk in the mix. I'd just watch the alkalinity and pH for a bit, and see how the parameters response. Watching the calcium isn't as useful due to accuracy limits in our test kits.

Kalk is saturated at 2 tsp per gallon of pure water. If your tank needs more than that, there are ideas to try, but 1 tsp is a good starting place.
 
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