Calcium levels after water change

[Slothwick]

Hi,

I have just done a 90% water change in my 800L tank with natural sea water.

After 24 hours I have just tested the Alk and calcium levels. The calcium is reading 320ppm.

How normal or abnormal is this? One of the big reasons behind this big water change was to increase the calcium levels to get a good starting point to buy corals.

 

[Big G]

Bump

 

[Bbfishb81]

What kind of salt do you use and are you using RODI water?

 

[Slothwick]

In the past I have mixed Red Sea coral pro and yes with RODI water.

But for this most recent 90% water change, I went to the ocean and got natural sea water.

I’m struggling to understand how within 24 hours of this change, my calcium levels could be so low. It is my understanding that almost all clean ocean water with have a calcium level much higher than that .

Can anyone give me a guide on what the calcium levels should be straight from the ocean? And also what, if anything, could cause the drop within 12 hours of being in the tank?

 

[Mickey]

Did you test the CA level of the ocean water before you put it in the tank? In other words, are you sure there was a drop in levels? Depending on where you get the water from, the levels could be different than the average ocean levels.

 

[Randy Holmes-Farley Verified Community Expert]

In the past I have mixed Red Sea coral pro and yes with RODI water.

But for this most recent 90% water change, I went to the ocean and got natural sea water.

I’m struggling to understand how within 24 hours of this change, my calcium levels could be so low. It is my understanding that almost all clean ocean water with have a calcium level much higher than that .

Can anyone give me a guide on what the calcium levels should be straight from the ocean? And also what, if anything, could cause the drop within 12 hours of being in the tank?

Calcium does not rapidly change, but test error is common.

 

[Greg P]

What are your Alk and Mag levels?

NM, just saw the original posting date ...

 

[Slothwick]

Thanks for the replies. I’m going to put it down to test error and get myself a new calcium tester.

I hadn’t thought to test the NSW before hand. Will keep it in mind next time.
Cheers

 

[Barb0713]

Did you test the CA level of the ocean water before you put it in the tank? In other words, are you sure there was a drop in levels? Depending on where you get the water from, the levels could be different than the average ocean levels.

I live in Michigan and just find it absolutely amazing that you can go get water from the ocean that’s awesome. These lakes won’t work lol. I have to use RO…. But that’s pretty sweet.