Very High Calcium and Low alkalinity, HELP!!

[Larry101]

My alkalinity is currently at 7.3 which is low as it usually sits around 8.5DKH. And My calcium is off the charts on the salifert test kit, so I then used the low-resolution version and it says 600ppm. I created a different thread 3 days as I thought it was just my alkalinity that was low (my alk was at 6.7DKH a couple of days ago). I was previously using an API test kit for calcium at it says 420ppm for calcium, but I decided to buy a salifert one just to double-check, and sure enough, my calcium was off the charts today. I have been adding sodium bicarbonate slowly to raise the alkalinity as guidance from my other thread, but I am now seeking guidance as to what I should do. My alkalinity is at 7.3DKH and my calcium is at 600ppm.

 

[ZoixDark]

Have you tested magnesium?

 

[Larry101]

Have you tested magnesium?

No I currently have a Salifert magnesium kit coming in the mail. Do you think low mag could be the cause because I thought that low mag causes both calcium and alkalinity to precipitate out?

 

[Larry101]

BUMP!

 

[Randy Holmes-Farley]

Your alkalinity is perfectly fine.

I suspect the calcium is test error unless you dumped a lot in, but 600 ppm (if real) is not a huge problem.

Personally, I'd just make sure alk stays at at least 7 dKH with baking soda while the calcium declines.

Try measuring th4 calcium in your new salt water.

 

[Randy Holmes-Farley]

Have you tested magnesium?

It's always fine to test things, but no level of magnesium contributes to high calcium.

 

[Larry101]

Your alkalinity is perfectly fine.

I suspect the calcium is test error unless you dumped a lot in, but 600 ppm (if real) is not a huge problem.

Personally, I'd just make sure alk stays at at least 7 dKH with baking soda while the calcium declines.

Try measuring th4 calcium in your new salt water.

No I did not add any calcium as I haven’t dosed ever to my tank. My normal alkalinity in my tank was always around 8.5. Yeah I do think 600ppm could have definitely have been a testing error as I had to go with the low resolution mode on the salifert test kit since my number is for sure over the 500ppm mark.

 

[Randy Holmes-Farley]

No I did not add any calcium as I haven’t dosed ever to my tank. My normal alkalinity in my tank was always around 8.5. Yeah I do think 600ppm could have definitely have been a testing error as I had to go with the low resolution mode on the salifert test kit since my number is for sure over the 500ppm mark.

Just use a second syringe of titrant in the normal Salifert method, and add the two values together.

 

[Larry101]

Just use a second syringe of titrant in the normal Salifert method, and add the two values together.

Ok, my calcium is at 575 ppm after doing this method. Now I will test my new tank that is currently cycling that I just filled up with water a couple of days ago. This should hopefully give me an accurate reading of my salts parameters.

 

[Larry101]

The salifert test says that my new tank is at 560ppm. Could the salifert test possibly be inaccurate? I was using an API test in the past and it says 420-440ppm.

 

[stanleo]

My tank was over 500 for the first year of its life. Then finally it started dropping which I think is a result of the coraline algae taking off and using it up more than my soft corals. I didn't have any hard corals at that time. Then once I finally figured out how to get my alkalinity stable with an auto doser and the calcium started dropping at a predictable rate. Then I started dosing for calcium. I use Soda Ash from BRS to keep alk stable and sodium chloride from BRS for calcium. I think if you can get your alk stable at 8.5-9 and wait a couple weeks you will start seeing a drop in calcium.

 

[Randy Holmes-Farley]

I expect your salt mix at the salinity you are using is at that level.

I'd just maintain alk as needed with baking soda until the calcium declines.

 

[Larry101]

My tank was over 500 for the first year of its life. Then finally it started dropping which I think is a result of the coraline algae taking off and using it up more than my soft corals. I didn't have any hard corals at that time. Then once I finally figured out how to get my alkalinity stable with an auto doser and the calcium started dropping at a predictable rate. Then I started dosing for calcium. I use Soda Ash from BRS to keep alk stable and sodium chloride from BRS for calcium. I think if you can get your alk stable at 8.5-9 and wait a couple weeks you will start seeing a drop in calcium.

Thanks for the advice, I think I will actually go ahead and do this!

 

[ZoixDark]

It's always fine to test things, but no level of magnesium contributes to high calcium.

Slightly off topic but for my knowledge/clarification. I could be totally wrong and I'm fine with that, Mag keeps calcium from precipitating correct? I'm guessing there's a limit to how much calcium can remain in solution for a given mag amount.

 

[Randy Holmes-Farley]

Slightly off topic but for my knowledge/clarification. I could be totally wrong and I'm fine with that, Mag keeps calcium from precipitating correct? I'm guessing there's a limit to how much calcium can remain in solution for a given mag amount.

Like organics and phosphate, magnesium helps stop the abiotic precipitation of calcium carbonate by getting onto the growing crystal surface and disrupting the exposed area, making it look less attractive for more calcium and carbonate to precipitate. Low pH also helps by reducing the concentration of carbonate.

Very low magnesium can contribute to the likelihood of precipitation calcium carbonate, reducing alk and calcium in the ratio of about 2.8 dKH of alkalinity for each 20 ppm of calcium.

Normal magnesium inhibits that process (doesn't stop it, just slows it).

Elevated magnesium inhibits the process to a greater extent.

With that process in mind, it is clear that there's no level of magnesium that can cause calcium to become elevated with alkalinity remaining normal.

 

[ssunthar]

Your alkalinity is perfectly fine.

I suspect the calcium is test error unless you dumped a lot in, but 600 ppm (if real) is not a huge problem.

Personally, I'd just make sure alk stays at at least 7 dKH with baking soda while the calcium declines.

Try measuring th4 calcium in your new salt water.

I have a similar problem too... while my other parameters are ok, I could not bring my calcium down. You mentioned baking soda, any guide on how much to add? And can it be any baking soda or need to be a specific brand? Thanks.

 

[Alex Cataldo]

No I currently have a Salifert magnesium kit coming in the mail. Do you think low mag could be the cause because I thought that low mag causes both calcium and alkalinity to precipitate out?

Yes magnesium is what keeps those ions from coming together. Honestly if it’s that bad I would recommend doing a water change to stable everything out while you wait for the test kit in the mail.

 

[rusgum]

I have a similar problem too... while my other parameters are ok, I could not bring my calcium down. You mentioned baking soda, any guide on how much to add? And can it be any baking soda or need to be a specific brand? Thanks.

You are checking your test with a reference fluid. Deviations can be up to 150 units and these corrections must be made during measurement.

 

[Randy Holmes-Farley]

I have a similar problem too... while my other parameters are ok, I could not bring my calcium down. You mentioned baking soda, any guide on how much to add? And can it be any baking soda or need to be a specific brand? Thanks.

Let's back up.

Exactly what problem do you have? Why do you want to reduce calcium?

 

[lazy josh]

Let's back up.

Exactly what problem do you have? Why do you want to reduce calcium?

My tank is new and from what ive read Randy say over and over again just to keep alk stable and no corals or very few just use baking soda and ive been doing that since my calcium doesnt change since nothings using it and my tank has been great and i do a water change only when nitrates get to 20 ppm other then that just mix a little baking soda with some tank water

less is more try doing 1/16th teaspoon of baking soda if it stays the same do an 1/8th and just check you will find how much you need to keep it stable at your 7.3dkh

id dose a very small amount of baking soda and re test the next day after doing that i figured out i only need like 1/16th of a teaspoon every 3 days to keep my alk pretty stable in between water changes

i maybe wrong in how i did it but your better off starting very small and uping the dose slowly until you get it stabalized

i hope i helped and didn’t give any wrong info
Just my personal experience and learning from R2R everyday =]