Kalk snowstorm...

[Brad]

My tank has been steadily increasing the amount of calcium it consumes. I have been dosing with Kent AB, but it has gotten to the point where I have to add substantial amounts, and I just can't spread the additions throughout the day enough.

So I decided it was time to go to kalk.

I setup a dripper and began to add the kalk. I tested the drip rate for a few days first to make sure I had a rate that was close to evaporation rate. My final Cal/Alk measurement was 360/3.3mEq. I thought I would drip for 12 hours or so, then take another measurement.

The kalk was mixed at 1 tsp per gallon, and left to sit for about 3 hours.

ANYWAY.... it was less than 1 hour that I began to notice small particles in the water. I stopped the drip and within 15 minutes they were gone. The drip system does not draw kalk from the bottom of the container.

I've read about the possibility of Ca precipitation if you overdose kalk, but I can't believe that 1 hour of dripping could possibly have OD'd the system....and my Ca was reasonably low to begin with.

My Ph test kit isn't that accurate, but the Ph of the system seems to be about 8.

Any ideas?

 

[malkore]

Keep in mind I am new too, and haven't started my kalk drip...

everyone tells me you add your kalk powder to a gallon, mix it, and let it sit 12-24 hours.
Then you drain off the top water, leaving any un-mixed sediment behind.
your mixing strategy could be playing a part in this.

Also, I too have heard about calcium precipitating out of solution. I don't think it's necessarily 'an overdose' of kalk, but rather something else (magnesium???) that's not allowing the calcium to stay in solution.

 

[jackdp]

If this is in the 30 gallon tank in your profile, it might not take long to supersaturate the tankwater with Ca by dripping saturated kalkwasser. Dripping kalk in such a small tank will also quickly drive the pH up which could also cause precipitation of calcium carbonate. I would closely monitor the pH, preferably with a pH monitor when adding kalk to such a small system. Read the limewater section of this article and see if it helps any...

http://www.advancedaquarist.com/issues/feb2003/chem.htm

 

[Sparky]

I read an article on calcium in the tank. If I remember right it said something about the rest of your readings specifically pH and Alk being out of wack, can make the calc readings actually go lower even though you are adding calcium to the tank water. The snow is from saturation I think. Let me find the article and post the link or the article itself for you to read. I found it pretty interesting. I also may have all this mixed up to. I will find the article.


http://advancedaquarist.com/issues/july2002/chem.htm

This is one of the articles I had found.

Mike

 

[Brad]

Thanks for the advice. I've read both those articles...I don't think the 2nd one applies as it discusses the addition of Calcium Carbonate, not Calcium Hydroxide.

I'm going to assume that I didn't let the solution sit long enough and try again.

 

[Brad]

Nope, even after 48 hrs of sitting...the moment I begin to drip in the kalk the tank starts to get cloudy with very small particles floating around.

Is kalk supposed to be clear? Because my mixed kalk solution is sort of milky, cloudy looking. It stays cloudy even though I haven't stirred it in days.

Should I allow the kalk to breath? It is being kept in a sealed container.

It seems to me that the cloudiness I'm seeing in the tank is a natural reflection of dripping a cloudy substance into the water.

Something isn't right here.

 

[steve-s]

Try putting it in the fridge after mixing it with the lid on. It really shouldn't make much difference but you never know. It could be a CO2 problem.

Is the pH continuously 8 and what's the water flow in the tank?

Cheers
Steve