Determining Ca usage.

[deep6er]

What is the best way to determine Ca usage in a sps tank.

[kgross]

Measure the Ca level over a time period with no supplementation.

Ie Measure Ca level day one, with no kalk reactors/Ca reactors or other calcium supplements dosed, measure Ca level on day 2. If there is a measurable difference that is the usage per day. If the difference is not measurable, check levels a few days/week later with no supplementation.


After this you will need to do a one time dosage of CA and Alk to bring levels back up before you go back to regular dosing.

[Randy Holmes-Farley]

Why do you want to determine it?

If it is for supplementation dosage determination purposes, trial and error may be better than going without and watching the drop as the usage depends on the pH and the alkalinity, which in turn are often changing if you are not supplementing.

[deep6er]

<a href=showthread.php?s=&postid=13743655#post13743655 target=_blank>Originally posted</a> by Randy Holmes-Farley
Why do you want to determine it?

If it is for supplementation dosage determination purposes, trial and error may be better than going without and watching the drop as the usage depends on the pH and the alkalinity, which in turn are often changing if you are not supplementing.
I want to see how much Ca my tank uses up. Then supplement the proper amounts. Reson for this is im having trouble keeping Ca, Kh, and Mg somewhat stable
eg. tested on Wednesday
Ca 420
Kh 12.4
Mg 1350

tested Thursday
Ca 400
Kh 12.4
Mg 1200

I do have a Ca reactor

[Randy Holmes-Farley]

OK, as I suggested, that will only be a rough guide, and trial and error when actually using a supplement is a better way to gauge dosing. :)

If you have a reactor, why are you concerned with supplements at all?

[deep6er]

<a href=showthread.php?s=&postid=13745626#post13745626 target=_blank>Originally posted</a> by Randy Holmes-Farley
OK, as I suggested, that will only be a rough guide, and trial and error when actually using a supplement is a better way to gauge dosing. :)

If you have a reactor, why are you concerned with supplements at all?

ok i'll try that.
I'm thinking I don't have it dialed in proper. My Ca levels seem to fluctuate to much. And the only way i can get my Ca back up is to supplement

[Randy Holmes-Farley]

If the reactor is maintaining alkalinity, then it must be maintaining calcium. I presume alkalinity is OK without adding buffers?

if calcium is moving around, it is either testing error, or being driven by water changes with a mix that is higher or lower than the tank water. :)

[deep6er]

<a href=showthread.php?s=&postid=13746683#post13746683 target=_blank>Originally posted</a> by Randy Holmes-Farley
If the reactor is maintaining alkalinity, then it must be maintaining calcium. I presume alkalinity is OK without adding buffers?

if calcium is moving around, it is either testing error, or being driven by water changes with a mix that is higher or lower than the tank water. :)
I think the problem was or is, is that my Alkalinity was to high. 13.1, Ca 370. and my Mg was at 1260. I have resently changed to deltec salt. and have noticed that the Ca, Kh,and Mg are starting to look more in the range of where i want them to be.
But like you said if my Ca reactor is working proper i should not need to add suppliments. Im going to change the media in it tonight and adjust it over the next few days. We'll see where things go from there.

Thanks

[Randy Holmes-Farley]

OK, sounds good.

Good luck. :)