Kalkwasser already at its limit.

[Aquajan]

Hi,

I have a tank thats running for 5 months now and around 1 month with corals.
I use kalkwasser and 10% weekly wc to keep parameters in check but now I already seem to hit the kalks limit.
My ph is now peaking at 8.37 so I think I shouldn't go higher.

The system is 90g total water volume.
I dose 2280 ml of saturated kalk each day (24x95ml).
That's 1.2 grams of kalk per day.
Or 0.76 kh per day and 5.3 ca per day (I think).

I read that kalk would probably be all I needed the first year so is now question myself..
Is this a normal daily consumption or am I precipitating alot?

I do not have any coraline growing yet as I just introduced it on a frag rock 3 weeks ago.

The corals are all frags.
2x sertiopora
3x montipora digata
2x Monti plate
1x Acro green slimer
1x Eyphillia
1x Ducan
1x Caulastrea

Kh 8.2
Ca 430
Mg 1350
Sal 1.025
No3 8
Po4 0
Temp 25

 

[miyags]

Wow, I only use a 1/2 teaspoon of pickling lime per gallon of RO top off, a night.and my Alk is around 9.7 and my Cal is high around 450 or higher.65 gal.cube tank with about 10 favia frags and a few 5in hammer colonies. 3 large favias, 3in chalice,5in candycane colony bublegum monti and a elegance coral

 

[Silent]

If you want to get a little extra mileage out of your kalk you can add vinegar to the mix and it lets you use more kalk to increase alk a little more. You might be able to hold off dosing for a couple months with that method.

 

[Aquajan]

Yea I know that method with vinigar, but as it is a carbon source and I'm using nopox already I don't want to go that route but thanks anyway for pointing that out.

I have the gear and reagents to do 2 part.
And the idea was to start with kalk and when it hits its limit to dose kalk to aim for a peak ph of 8.3 and than just dose 2 part on top of that.

But to make my question a little more specific.

Is a kh drop of 0.76 a day normal with my coral stocking and the age of the tank?

 

[biophilia]

0.76 DKH daily draw seems fairly normal to me for a tank with a moderate amount of stony corals — even in the absence or coralline. It’s not abnormal for tanks to draw 1-3DKH or more daily once growth picks up (even soft drinks coral dominated tanks if there’s a lot of coralline growth)

 

[Rybren]

Something seems off to me. I believe it takes 2 teaspoons per US gallon (~3785ml) to achieve a saturated Kalk solution. A teaspoon of Kalk weighs roughly 12 grams, so 2280ml of saturated kalk solution should provide roughly 14.5 gms of Calcium Hydroxde.

I doubt that your tank is using that much right now. My current tank is 5 years old and it doesn't use that much.

Are you sure that you're using a saturated solution?

I might be tired and way off, but something doesn't jive with me.

 

[Aquajan]

Omg u are right ;Facepalm
I don't know where I got that 2 grams = 1 teaspoon..
Im Indeed not near a saturated solution.

Thanks for noting that.

Im using kalk from deltec witch has no discription...
But seachem says 6 grams in 1 gallon rodi for a saturated solution.
I assume all brand use pretty mutch the same stuff..

 

[Rybren]

I used an online calculator to find out the weight of Calcium Hydroxide, and it came up as 11.53 gm per teaspoon. According to RHF, it takes 2 teaspoons per gallon for saturation, so that would be 23.06 gm

I don't know what the Seachem product is, but if it's Calcium Hydroxide, then either their directions are off or the calculator is off.

 

[Rybren]

I used an online calculator to find out the weight of Calcium Hydroxide, and it came up as 11.53 gm per teaspoon. According to RHF, it takes 2 teaspoons per gallon for saturation, so that would be 23.06 gm

I don't know what the Seachem product is, but if it's Calcium Hydroxide, then either their directions are off or the calculator is off.

I did some more searching and I think that the calculator is off. If 6 gm is required for saturation, then 2280 ml of saturated solution would provide 3.6 gm of Calcium Hydroxide

 

[Aquajan]

Yea indeed, I've found another calculator that confirms the 6gr per gallon ratio.

Kalk Contribution Calculator

Aquarium calculator; Estimate the contribution of a kalk solution towards the calcium and alkalinity of a system.

www.hamzasreef.com

I will add 3x as mutch with the next batch and than dose 1/3 from wat ik dosing now.
I wonder if the 3x more potent solution will also have 3x more effect on ph..
I will find out next weekend.

Thanks for the help

 

[nereefpat]

The effect on pH will be the same if the total weight of dry lime is the same. I forget the ratio, but X amount of dKH increase = Y amount of pH increase.

Just playing around with a calculator, you should be able to get closer to 1.5 dKH per day with kalk, assuming about 90 gallons and evaporation of about 1 gallon per day.

 

[Randy Holmes-Farley Verified Community Expert]

Hi,

I have a tank thats running for 5 months now and around 1 month with corals.
I use kalkwasser and 10% weekly wc to keep parameters in check but now I already seem to hit the kalks limit.
My ph is now peaking at 8.37 so I think I shouldn't go higher.

The system is 90g total water volume.
I dose 2280 ml of saturated kalk each day (24x95ml).
That's 1.2 grams of kalk per day.
Or 0.76 kh per day and 5.3 ca per day (I think).

I read that kalk would probably be all I needed the first year so is now question myself..
Is this a normal daily consumption or am I precipitating alot?

I do not have any coraline growing yet as I just introduced it on a frag rock 3 weeks ago.

The corals are all frags.
2x sertiopora
3x montipora digata
2x Monti plate
1x Acro green slimer
1x Eyphillia
1x Ducan
1x Caulastrea

Kh 8.2
Ca 430
Mg 1350
Sal 1.025
No3 8
Po4 0
Temp 25

The pH peak is not a concern. My tank ran 8.35 to 8.55 for years.

More aeration will also lower it, if you are still concerned.

 

[Randy Holmes-Farley Verified Community Expert]

Yea indeed, I've found another calculator that confirms the 6gr per gallon ratio.

Kalk Contribution Calculator

Aquarium calculator; Estimate the contribution of a kalk solution towards the calcium and alkalinity of a system.

www.hamzasreef.com

I will add 3x as mutch with the next batch and than dose 1/3 from wat ik dosing now.
I wonder if the 3x more potent solution will also have 3x more effect on ph..
I will find out next weekend.

Thanks for the help

The effect of limewater on pH will depend on how quickly it is added.

1.4 dKH added instantly will boost pH around 0.7 pH units. Way too much for instantaneous addition.

Spread that out over a whole day and the effect is far smaller since the tank brings in CO2 from the air during that time.

 

[Aquajan]

I dose kalk 24x a day so that should be spread out enough.

I placed my wavemakers more to the surfice yesterday and now the ph dropped from 8,21 to 8,05..
That did the trick
Now I can add loads more.

Thanks

 

[Randy Holmes-Farley Verified Community Expert]

Sounds good. Happy Reefing

 

[sayurasem]

I dose kalk 24x a day so that should be spread out enough.

I placed my wavemakers more to the surfice yesterday and now the ph dropped from 8,21 to 8,05..
That did the trick
Now I can add loads more.

Thanks

I’m having issues with suppressed ph during winter time. I’ve been dosing kalkwasser for the past week and it helped a bit. I always thought more surface agitation will help oxygenate the water and thus raises ph.

This blew my mind. I will lower my wave maker and return flow to see if it bump the ph a bit more.