# Calcium levels through the roof



## Omis (Dec 27, 2010)

For the last week or so my calcium has been over 600 for some reason. I haven't dosed cal at all. The levels aren't dropping at all which I find strange. I'm dosing alkalinity to keep it around 8dkh but it wants to keep falling to 7.

I did a big water change with reef crystals, maybe I have a bad batch?


----------



## caker_chris (Apr 22, 2010)

what test kit are you using?


----------



## Omis (Dec 27, 2010)

I have 3 different test kits, Salifert, Red Sea and Seachem. All say pretty much the same thing.

My corals and fish look better than ever though. Weird.


----------



## wtac (Mar 17, 2006)

What is the Mg?


----------



## Omis (Dec 27, 2010)

Mag is at 1410, ph is 8.1


----------



## Chromey (Sep 25, 2010)

coralife salt?


----------



## Omis (Dec 27, 2010)

I/O reef crystals


----------



## Chromey (Sep 25, 2010)

SOmethings off, RC Mix at 380 to 440... Are you testing it right?

Are you topping off with Fresh RO water or Saltwater?


----------



## Omis (Dec 27, 2010)

Testing is right. RO top off of course. 

Im going to mix up a small batch to see if its the salt mix. The only other thing I can think of is that I added a phosphate reactor to get algae under control without adjusting my calcium supplement initially. Maybe the algae was consuming more of the calcium than I suspected? In fact, my coraline doesn't seem to be growing much at all lately despite the high cal levels.


----------



## wtac (Mar 17, 2006)

If you are using and iron oxide PO4 removing media, ie ROWA, TLF, "fresh" media will drop kH and throw the Mg/Ca/kH out of balance.

One of my clients after changing ~2cp of ROWA dropped the kH to 6 from 8 and Ca is raised from 410 to 525mg/L in his 220gal mixed reef using TMP salt. After ~month it went back to typical range and no adverse affects to the coral.

JME/HTH


----------



## carmenh (Dec 20, 2009)

So is there any way around this swing if when starting/replacing phosphate removers?



wtac said:


> If you are using and iron oxide PO4 removing media, ie ROWA, TLF, "fresh" media will drop kH and throw the Mg/Ca/kH out of balance.
> 
> One of my clients after changing ~2cp of ROWA dropped the kH to 6 from 8 and Ca is raised from 410 to 525mg/L in his 220gal mixed reef using TMP salt. After ~month it went back to typical range and no adverse affects to the coral.
> 
> JME/HTH


----------



## Omis (Dec 27, 2010)

wtac said:


> If you are using and iron oxide PO4 removing media, ie ROWA, TLF, "fresh" media will drop kH and throw the Mg/Ca/kH out of balance.
> 
> One of my clients after changing ~2cp of ROWA dropped the kH to 6 from 8 and Ca is raised from 410 to 525mg/L in his 220gal mixed reef using TMP salt. After ~month it went back to typical range and no adverse affects to the coral.
> 
> JME/HTH


Thats interesting, I've never heard this before. I'm using GFO from bulk reef supply. I thought you were supposed to change it once a month? I was going change the gfo with every water change but now I may reconsider.


----------



## wtac (Mar 17, 2006)

There are quite a few threads on RC and Randy Holmes-Farley explains it quite well on calcium carbonate precipitation and iron based (GFO) phosphate removing media.

Link
Link

Other reefers have also observed kH/alk drops using GFO phosphate removers:

Link
Link

As I mentioned before, there is a close relationship of equilibrium of Mg, Ca and kH/alk. When one is "off" it will throw one or the other two off. As each system is different, the degree it is affected and "bounce back to normal" will differ from one system to another as no two systems/aquariums are alike. There are a few variables to take into consideration and one can't predict "Mother Nature".

IME w/changing GFO, it's six of one, half dozen of the other. Either use less GFO, keep the flow rate through the reactor the same and change more regularly OR use more GFO, reduce the flow rate in the beginning, increase flowrate over a period of time and change less often. It's going to be a PITA in one area or another...LOL!

It's just the nature of the beast, I'm afraid to say.

How often to change, that varies as well. A 400gal reef system with 2Lof RowaPhos, I haven't changed it in over a year and PO4 has maintained a steady @0.01-0.1. Another 220gal reef system I change 250mL of RowaPhos every 2 months when PO4 creeps over 0.1mg/L from the previous service.


----------



## Omis (Dec 27, 2010)

Thanks for the info wtac, it was very enlightening.


----------

