Calcium dropping alk stable

[Clownfishy]

I have been using Randy's two part for a few months now with great success. However, I needed to change my salt from Reef Crystals due to high Zinc levels. I switched to H2Ocean Pro and since then my Calcium has been dropping while my Alk staying constant. I have started to have to increase my calcium dosage to prevent it dropping below 360.
Alk 11.2
Calcium 360
Mag 1490

Alk dosage 29ml per day
Calcium dosage 35ml per day


A few questions -
1). Would a rise in pH from 8.30 to 8.40 impact this

2). Does calcium loose it's potency? It has been in the dosing container for a few months and it is pretty airtight but obviously some air gets into it.

3). I have tested with 2 separate test kits and get the same reading is there anything else I should check?

 

[Triggreef]

I need to add ca a couple times a month too.

 

[Clownfishy]

I need to add ca a couple times a month too.

I am having to add far more calcium on a daily basis just to stop it dropping so I am beginning to wonder if the solution degrades over time. I think I will mix some more calcium and use that to see if this is the reason why I need more calcium than alk.

 

[Clownfishy]

@Randy Holmes-Farley , quick question, can the calcium element of your 2 part mix loose it's potency? I am now dosing double the amount of calcium and cannot move my calcium above 370. Just wondering if it becomes less effective the longer you store it? I made it up a few months ago and a small amount of air must get into the dosing container so would calcium precipitate out or some other reaction be happening?

Will make up a fresh batch this weekend to see if this helps.

 

[Clownfishy]

Just for information, made up some new Calcium Chloride and it didn't make any difference. I am now dosing
30ml Soda Ash
80ml Calcium Chloride. So far I have managed to get my Calcium up to 375.

 

[Randy Holmes-Farley Verified Community Expert]

Should be easy to boost it to your target in a couple of days. [emoji3]

 

[Clownfishy]

Thanks @Randy Holmes-Farley , it does not seem to matter how much I add, Calcium does not seem to rise. Today, I dosed 30ml of Soda Ash and added 105ml Calcium Chloride. My testing today is
Calcium 370ppm (down from 375ppm in 24 hours)
Alk 11KH (up from 10.9KH)
Mag 1365 (down from 1395)

Just added some BIO Magnesium to boost Mag a bit higher. I am also dosing another 30ml today but worried to dose much more today.

Have you seen this type of thing before and is there a risk of keep dosing way more Calcium Chloride than Soda Ash?

 

[Tmmste]

That is weird.. do you leave enough time between kH & Ca dosing? And are you dripping the solution in a high flow area ? It should not magically disappear unless it precipitated and formed calciumcarbonate for some reason.. or maybe the testkit is no longer reliable.

 

[Clownfishy]

I dose about 5 minutes between Calcium and the Soda Ash right above the Tunze stream. I dose over a 4 hours during the morning and another 4 hours in the evening. Tested 2 different test kits as I just brought a brand new test kit.

Just added another 30ml and my Calcium increased to 375/380ppm. The things that I can think have changed which may be influencing this is my pH is now consistently sitting at 8.30 (was 7.90) and I changed salts from Reef Crystals to H2Ocean Pro. Not sure why either of these would affect juat Calcium and not Alk though.

 

[Randy Holmes-Farley Verified Community Expert]

There is nothing that can stop calcium from rising if you add enough calcium chloride only. You certain it is calcium chloride and not a different calcium additive?

 

[Randy Holmes-Farley Verified Community Expert]

It’s not Biocalcium?

 

[Clownfishy]

Definitely Calcium Chloride and was maintaining the Calcium up until the rise in pH and change of salts, although that my just be coincidence.

 

[Clownfishy]

 

[jduong916]

I had the same problem in my tank. I always had to dose way more calcium. I was using the driveway pellet calicium chloride, this solution just wasn't equal strength of the soda ash solution. I've started using BRS bulk and the dosing between Calcium and Alkalinity are pretty even now.

I kind of don't trust what they write on the package of some of these chemicals. I think I used Joes Snow melt and it said 89% calcium chloride. But the dosing solution wasnt as potent as it should have been.

 

[Tmmste]

I dose about 5 minutes between Calcium and the Soda Ash right above the Tunze stream. I dose over a 4 hours during the morning and another 4 hours in the evening. Tested 2 different test kits as I just brought a brand new test kit.

Just added another 30ml and my Calcium increased to 375/380ppm. The things that I can think have changed which may be influencing this is my pH is now consistently sitting at 8.30 (was 7.90) and I changed salts from Reef Crystals to H2Ocean Pro. Not sure why either of these would affect juat Calcium and not Alk though.

Hmmm.. I would say give it 45 minutes between Ca and kH dosing.. I usually created a snowstorm in my tank dosing one part a few minutes after the other.. although if you take 4 hours to dose the stuff I would say hardly anything precipitates.. Maybe the salt batch is a mixed uneven? I would personally wait with doing a water change and first see if the dosing works. If you need to boost Ca you can also add x amount to your topoff water (else 1 jug will be more empty than the other one).

40,078 / 0,27261= 147 gr of your calcium chloride dihydrate will boost you Ca with 40.078 ppm per liter aquariumwater. So that is 400 ppm per 100l... if you want to go from 420 to 460 ppm.. you need 40 ppm. Per 100 liters you would then need 14,7gr calciumchloride. E.g. if you tank is 500 liters.. you add 14,7 x 5 = 73,4 gr of calciumchloride dihydrate to your topoff water...

check calculation: 73,4gr * 0,27261 = 20036 ppm calcium per 1 liter = +200 ppm per 100 liter = + 40ppm per 500 liter.
See: https://www.convertunits.com/molarmass/CaCl2.2H2O

As long as it is spread across a number of days you are going to be just fine. Good luck!

 

[Clownfishy]

Many thanks for the replies. I am beginning to think the strength of the Calcium chloride is not what it should be as suggested above. I am now dosing -
150ml Calcium Chloride
30ml Alk

My calcium is staying at 375/380 so I will dose at this level for another day but also look to purchase a different brand of calcium chloride.

 

[Clownfishy]

Anyone know what the "food grade percentage" we should be using for Calcium Chloride as the only one I can seem to purchase states -

"Calcium Chloride - Very Pure Food Grade 77% Dihydrate Flake"

 

[Clownfishy]

Ignore last post, I have just reread Randy's instructions and 77% should be fine

 

[Clownfishy]

Just dosed another 30ml and at long last, I have my calcium up to 395 and my Alk at 11.2DKH. It took a 24 hour dosage of -
170ml calcium chloride
30ml soda ash

I will test tomorrow with this level of dosage for another day and report back.

 

[Tmmste]

Just dosed another 30ml and at long last, I have my calcium up to 395 and my Alk at 11.2DKH. It took a 24 hour dosage of -
170ml calcium chloride
30ml soda ash

I will test tomorrow with this level of dosage for another day and report back.

Did you use 500gr per gallon? If so = 132gr per liter = 36000 ppm. 170 ml = 1080 ppm / 190 liter = + 32.2 ppm max if you wouldn't have any corals consuming the calcium between the moments of testing.

So the 15 to 20 ppm increase would be possible. If the tests are accurate and the solution exactly 500gr per gallob. Then you have an idea now what your corals are consuming... next time measure if you see a 32 ppm increase some time after you dosed...