Understanding parameters

VicZA

VicZA

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So we try to make our water as suitable as possible for our little marine friends and we test and measure Calcium, Magnesium, Alkalinity, pH, etc .....

However, I still do not fully understand how the 3 basics (Ca, Mg, KH) are "consumed" by the tank

I assume the Calcium is consumed by the skeletons of the SPS and LPS, but what consumes KH and Mg and hence why do we need to dose these ....
 
my limited understanding of why these need to be added is so that the actual cal mag or whatever in the symetry can actually dissolve one another to be able to be taken up by the animal, by adding one and not the other (cal without mag for eg) the cal is unavailable as precipertation will occur rendering it in a state of limbo..

very basic explination but thats the jist of it,

keep in mind cal alk ph and mag work together, and need to be dosed proportionally...
 
my limited understanding of why these need to be added is so that the actual cal mag or whatever in the symetry can actually dissolve one another to be able to be taken up by the animal, by adding one and not the other (cal without mag for eg) the cal is unavailable as precipertation will occur rendering it in a state of limbo..

very basic explination but thats the jist of it,

keep in mind cal alk ph and mag work together, and need to be dosed proportionally...
 
I had very low ALK (5.3dkH) and very high Ca (525ppm). I have raised my Alkalinity and it is now fluctuating between 7.5-6 dKH and yet my Calcium will not drop from 525ppm. SO should I raise the ALK to be "in balance" with a high Calcium ?
 
Kh is not just consumed by the coral. What ever breaths, eats, filters water or make a dump will affect your Kh. Carbonate Alkalinity (kh) is as imortant as any of the basic parameters. I would recommend a higher level than your current kh level and I would raise it to round 8.2. Then you should keep it there as it is consumed much faster than Ca or Mg. In any Lps and Sps kh and Ca are used as the building blocks for the skeleton and the chemical composition is then referred to as CaCo2. CaCo2 is the hard stony structure. Thus in short if your kh is low your Ca will not drop as expected. Do not attempt to raise the kh in one dose to the required level of 8.2 but rather over 3 to 5 days. A sharp increased level is as dangerous as a low reading.
 
Snoek said:
Kh is not just consumed by the coral. What ever breaths, eats, filters water or make a dump will affect your Kh. Carbonate Alkalinity (kh) is as imortant as any of the basic parameters. I would recommend a higher level than your current kh level and I would raise it to round 8.2. Then you should keep it there as it is consumed much faster than Ca or Mg. In any Lps and Sps kh and Ca are used as the building blocks for the skeleton and the chemical composition is then referred to as CaCo2. CaCo2 is the hard stony structure. Thus in short if your kh is low your Ca will not drop as expected. Do not attempt to raise the kh in one dose to the required level of 8.2 but rather over 3 to 5 days. A sharp increased level is as dangerous as a low reading.
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Ok, makes sense. I was raising my KH using Bicarbonate of SOda and had some success. When I reached 7.3 (over a period of a week from 5.3) I stopped dosing and wanted my Ca to drop to around 420-450, so that I could then start "feed-dosing" a balance compound (probably Kalwasser). However the KH dropped and Ca remained the same.

According to the reef Chemistry Calculator, a ALK of 9dKH corresponds to a balanced Calcium of 425ppm - should I be aiming for this ?

Also, since my Ca=525 will it be consumed if the ALK is only 8.2 ?
The Reef Chemistry Calculator suggests that a balance is 500ppm vs 20dKH !!

What does the "in balance" refer to ?
 
There is absolutely no advantage having Ca higher than 420. There are a number of reasons I personally would not run it higher than 420 but let's just say I dont like the idea some manufacturers try and pull the wool over our eyes. I started using kalk sometime ago but be warned there are risks linked to kalk. You need to monitor your ph very closely as kalk will raise it quickly if dosed incorrectly or to fast. If you use bicarbonate of soda make sure of the following: 1 only use pharmaceutical grade and not the normal food grade rabertsons bicarb. 2 make sure you bake it at 180deg for 30 min otherwise it will affect your ph.

I run a sps dominated tank and I dose kh every day. My dosing method is rather simple bur rather effective. I use a 4L juice jug and fill it with RO or tank water. I then add the required amount of bicarb and drip it over a 2.5 to 3 hour period via a airline with a cheap R2 valve.
 
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There is quick way to drop your Ca and its called a water change. Personally I would not stress to much about it however your coral will always give you a clear indication if its not happy. Your focus should shift to increasing your kh and once its round 8.2 to 8.4 to maintain it there. Stibility is key imo.
 
There is a benefit to keeping ca above 420, but no biological benefit to keep it above 380.
The benefit in keeping it above 380 is to have a safety margin.
Robertsons bicarb is pharma grade.
Be aware that in long run it will have a slightly lowering effect on pH.
Baking bicarb will cause it to affect pH, as the CO2 is driven off and the sodium bicarbonate becomes sodium carbonate, effectively causing an increase in pH.
The secret is to find the right balance of sodium carbonate and bicarbonate for your system.
N
 
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VicZA said:
So we try to make our water as suitable as possible for our little marine friends and we test and measure Calcium, Magnesium, Alkalinity, pH, etc .....

However, I still do not fully understand how the 3 basics (Ca, Mg, KH) are "consumed" by the tank

I assume the Calcium is consumed by the skeletons of the SPS and LPS, but what consumes KH and Mg and hence why do we need to dose these ....
Click to expand...

To answer your original question:
All three are consumed by a process called calcification, or biotic precipitation ie the skeletons / shells of sps lps, coralline algae, snails, hermits, some soft corals etc.
They are consumed in different ratios by different organisms, but as most calcification ratios of Ca:CO3:Mg:Sr are relatively close, replacing them in a balanced ratio is rather easy.
 
Ok, I have raised my Alkalinity now to around 8 dKH and my Calcium is 500ppm. Should I continue to dose Bi-carb so as to maintain the alkalinity at 8.1-8.2 and wait for the Calcium to drop to around 420-450 ?
 
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Essentially yes. Although bicarb not really the best option.
 
irie ivan said:
Essentially yes. Although bicarb not really the best option.
Click to expand...

Ok, I was thinking of Bicarb because of 2 reasons:

1 - I already have some
2 - I wanted the Calcium to come down so that I could then dose a compound like Kalwasser

Good or Bad idea ?
 
Bicarb will work for your alk, but there are better options. In essence, what you are wanting to will work. An avid kalk user myself, just read very carefully on the use thereof.
 
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