Low alkalinity and high calcium levels

[adromero]

Just tested my water today and my alkalinity continues to drop. It is now at 7.2 ppm from 8.0 ppm two weeks ago. It use to test near 10 ppm. I understand this happens when corals grow. I have been having great growth in a 34 gallon with SPS and LPS. However my calcium is at 520 ppm which grew from 440 ppm two weeks ago. Can I dose alkalinity twice a day because when I try to increase my alkalinity dose at one time my fish suffer. They begin to breath fast and some try to jump (I have a cover on my tank). I use the read sea recipe and dose 1.5 ml magnesium 12 ml alkalinity and 5 ml calcium daily with their product.

 

[nvictor]

Just tested my water today and my alkalinity continues to drop. It is now at 7.2 ppm from 8.0 ppm two weeks ago. It use to test near 10 ppm. I understand this happens when corals grow. I have been having great growth in a 34 gallon with SPS and LPS. However my calcium is at 520 ppm which grew from 440 ppm two weeks ago. Can I dose alkalinity twice a day because when I try to increase my alkalinity dose at one time my fish suffer. They begin to breath fast and some try to jump (I have a cover on my tank). I use the read sea recipe and dose 1.5 ml magnesium 12 ml alkalinity and 5 ml calcium daily with their product.

Sure. I have the same problem need to use a lot more alkali than calcium - i use the red seaa\ foundation a and b and I use many times more of the alkali than calcium with a doser.

 

[adromero]

Thanks for the reply.

 

[Randy Holmes-Farley Verified Community Expert]

Sure. I have the same problem need to use a lot more alkali than calcium - i use the red seaa\ foundation a and b and I use many times more of the alkali than calcium with a doser.

Be careful what you are claiming. The Red Sea product is not made for 1:1 dosing and using much more of the alk product is certainly expected. About 3x as much. It does not mean you tank deviates from the expected demand ratio of about18-20 ppm calcium for each 2.8 dKH of alkalinity.

 

[Randy Holmes-Farley Verified Community Expert]

Just tested my water today and my alkalinity continues to drop. It is now at 7.2 ppm from 8.0 ppm two weeks ago. It use to test near 10 ppm. I understand this happens when corals grow. I have been having great growth in a 34 gallon with SPS and LPS. However my calcium is at 520 ppm which grew from 440 ppm two weeks ago. Can I dose alkalinity twice a day because when I try to increase my alkalinity dose at one time my fish suffer. They begin to breath fast and some try to jump (I have a cover on my tank). I use the read sea recipe and dose 1.5 ml magnesium 12 ml alkalinity and 5 ml calcium daily with their product.

I presume the units of your alkalinity are dKH. In ppm it would be more like 125 ppm.

It is certainly fine to dose alkalinity alone if alk is dropping and calcium is rising.

 

[adromero]

Yes it is dkh. I convert the ppm by multiplying by .056. Sorry for the error on my original thread.

 

[Intense37754]

So if your alk is dropping your calcium will rise and then dosing alk to desired amount will lower calcium? Sorry, asking because we don’t dose and only do water changes to replenish

 

[ScottB]

Check your magnesium level while you are at it.

I 2-Part dose with ESV in even amounts. My Ca is always much higher 460-480 or so. When my ALK drops below 8.5 ish I will dose a bit extra.

 

[Randy Holmes-Farley Verified Community Expert]

So if your alk is dropping your calcium will rise and then dosing alk to desired amount will lower calcium? Sorry, asking because we don’t dose and only do water changes to replenish

Declining alk will not cause calcium to rise. Dosing alk does not cause calcium to fall.

Calcium and alk fall together as they are used to make calcium carbonate, such as shells or coral skeletons.