Dosing with Kalkwasser

rohnds

rohnds

Large Fish
#1
Apr 23, 2005
408
1
0
Austin, TX (born NYC)
#1
To increase my pH (8.2) level and Ca levels (390-400), I have being looking into dosing my tank with Kalkwasser. Everyone agree that dosing should be done very slowly over period of time. But the rate varies from author to author. Some suggest drip dosing the tank, at rate of one drop per second while other suggest adding an 5gal dose of Kalkwasser to your tank provided that the tank is at least 55gal in size. Yet others suggest adding Kalkwasser dosed water when you top off your tank.

My tank is 70gal with a 10gal sump(half filled). And I do about 10gal water change every other week. How much and how should I dose the tank? How does everyone dose their tank with Kalkwasser?

Rohn
 

T

TheFool

Large Fish
#2
Apr 19, 2006
323
2
0
#2
Well the absolute first thing to do is take pre and post water change Ca levels for abpit 6 weeks to work out tour current Ca usage. If you add Ca to roughly match that you'll be ok, if you exceed it a bit you'll still be ok and likely get greatcoralline, and if you go miles over you will 1. be wasting your money as most will precipitate out, possibly 'welding' your substrate, and 2. might throw mg out of whack. So don't go bonkers, but I think mild kalk dosing is a good idea for most tanks to raise alk.
If you have a high Ca demand then the trad method of getting fully concentrated CaOH solution and dripping it in is the way to go. If you add 5 gallons of fully conc limewater (kalkwasser) to a 55 you will kill everything I would imagine - but who ever adds 5 gals of makeup water to a 55 anyway. If you have a low usage, and what I do, is to add approx whats required to a litre of topup water and pour this directly into a high flow zone - this is sometimes described as a slurry method, and is described by both Calfo and Delbeek and Sprung. I add about a quarter teaspoon of kalk to a litre of water and dump it in 5 or 6 times a week. The pH level in this solution is nothing like high enough to be damaging. On the 7th day I tend to instead use a general alk builder to maintain levels of the other minor components of alk other than kH
 

rohnds

rohnds

Large Fish
#3
Apr 23, 2005
408
1
0
Austin, TX (born NYC)
#3
So you add a liter (~1/4 gal) of Kalk water directly into your all tank once?
Wouldn't a rapid addition of Kalk create CaCO3 rather than Ca++? From what I read, the only way to get around this is by introducing CO2 into your tank.
Are you running a CO2 diffuser?

Rohn
 

T

TheFool

Large Fish
#4
Apr 19, 2006
323
2
0
#4
What would adding CO2 do? By raising the number of CO3- ions you are surely increasing the chance of CaCO3 precipitation? In a calcium reactor adding the CO2 helps as you reduce pH to <7, but that is obviously not the case in the tank. Where did you reaf that, I'd be curious to see it.
But no, I don't add a litre of kalkwasser directly as I don't use fully saturated kalk, I don't have the calcium need to need to use it. I use an unsaturated solution. I have used fully saturated kalk and added it as a slurry on occasion. I didn't drip that, rather I poured it incrementally into a high flow zone to stop pptation, and pH spiking locally.
 

Lorna

Lorna

Elite Fish
#6
Mar 3, 2005
3,082
4
0
NE Indiana
#6
vinegar with allow more saturation of the kalk.....you really don't need to do that although it would lower the ph a bit as raising ph is not your objective but raising ca is. I used to dose kalk at the rate of 2 tsp/g and drip it using a persaltic pump. The kalk clogged up the drip tube so I quit using the kalk.....now I use Seachem Calcium Advantage......and mix it the same way...

I have read of using the slurry method but one shouldn't do that without the aid of a digital ph monitor as you want to ensure that your ph doesn't raise by more than .02 when you add it. That is why most people dose/drip kalk during the night as that is when the ph is lowest.......and the kalk has less effect on the ph. What ever method you chose you need to determine your actual ca usage and then add the kalk or additive to maintain it at that level. Dont use kalk to raise ca but to maintain it.....
 

rohnds

rohnds

Large Fish
#8
Apr 23, 2005
408
1
0
Austin, TX (born NYC)
#8
Dont use kalk to raise ca but to maintain it.....
Click to expand...
You are the 2nd person to suggest that Kalk doesn't actually rasie the Ca level?

How do you actually rasie the Ca level? I would ideally love to see my Ca level around 420 or even 450, for accelerated growth of SPS and coralline algae.

Up until now, I have being dosing the tank with SeaChem Liquid Calcium and it just doesn't seems to work.

Rohn
 

T

TheFool

Large Fish
#9
Apr 19, 2006
323
2
0
#9
Well you can raise the Ca levels with kalk if you add enough. However as even fully saturated kalk doesn't really contain that much Ca, if you have high usage then exaggerating levels just by using kalk as topoff water is not possible
There are penalties to really jacking up Ca, but what levels are you at now, and what's in your tank, how fast growing and so on. Note that coralline growth is very often stunted in sps tanks as comp for ca inhibits it's growth. You need to think 'whole tank'
 

Lorna

Lorna

Elite Fish
#10
Mar 3, 2005
3,082
4
0
NE Indiana
#10
I agree with The Fool.....no insult intended..... You need to determine what your actual ca usage is. Test your ca then wait 4 days then test again. Divide the difference by 4 and that will give you a ball park usage. Do this with alk/dh also as these two work in a fine balance. Then remember that to raise the ca you need to adjust your daily usage supplement upward slowly to raise it. If you don't have a high demand for ca in your tank I can't see why you want those levels......really a good level is around 400 as that is close to natural seawater. People that say their ca is 500 are wasting money as it can't be utilized .... how is the coraline in your tank? how old is the tank? what are the inhabitants.....how often do you do w/c etc. all these play into the calculations.....

This is a great calculator and will help I am sure

Reef Chemistry Calculator
 

T

TheFool

Large Fish
#11
Apr 19, 2006
323
2
0
#11
I like to stay around 400 too - going to really high levels might promote growth, but it is an abject pain to maintain, keep stable, plus a combination of that plus comparatively low flow gives you a whole load of aquarium corals with weak, fragile, brittle skeletons compared to wild corals
 

You must log in or register to reply here.