Very High Calcium and Magnesium. What is the best way to fix these?

[Curtis Scott]

I had my tank running on a dosing system for over a few weeks and thought I had it dialed in. Little did I know the calcium was over dosing. I noticed something was up with a few corals and decided to test the water out about 1.5 weeks ago.

 

Here is what I have today when I tested it again to see if things have improved at all since I stopped dosing:

 

Calcium = 550+ for over a 1 1/2 weeks, still the same level with no dosing since the initial test

Alk = 9.1 dkh I have been manually dosing this and checking it every day to make sure it stays right around 9-10 dkh

Magnesium = 1650ppm

 

I use reef crystals and just tested my newly made salt water and here is what I have, pretty normal:

 

Calcium = 450ppm

Alk = 7.9 dkh

Magnesium = 1450ppm

 

The tank is a 75g mixed reef w/ 20g sump and 25g refugium

 

I have water being made right now and plan to do a 30g WC tomorrow night or ASAP.

 

Few Questions:

 

What is the best way to approach this issue?

Are water changes really the only thing I can do at this point?

If so, how much of a water change is to much?

How often, is to often? Could I do a 30 gallon water change tomorrow followed by another one every 3 days until this is corrected and back to normal?

 

Sorry for all the questions but this is really freaking me out. My corals are showing signs of stress, which of course makes me stress. :\

 

I look forward to any advice you guys can offer. Thanks

Edited August 16, 2012 by Curtis Scott

[DaveS]

The Ca and Mg levels are high but not lethal. I would do a water change or two (don't need to freak out and do tons) and just let things settle down to normal levels over the next month or so. Do you have much in the way of Ca absorbing corals? If not, it will take a little longer to come down than if you do. Either way, it's nothing to freak out about. Just keep an eye on your Alk as you deplete the Ca and Mg. You don't want that to fall too low while the others are coming down. It's a balancing act between the 3 and once you get things dialed in correctly it will be easy. I sometimes find I need to add one or more of the 3 to keep things at the right level.

[surf&turf]

Or, you could do nothing but monitor your Alk, the Cal and mag will come down on their own.

[zygote2k]

Or, you could do nothing but monitor your Alk, the Cal and mag will come down on their own.

+1. Track how fast all 3 drop and you can begin to figure out your consumption rate.

[Curtis Scott]

Thanks guys! I'll move forward with the 30g WC tomorrow, then plan to track all 3 by testing every day at the same time.

 

Very reassuring that these are not at lethal levels yet. Thanks again.

[angel not fish]

Or, you could do nothing but monitor your Alk, the Cal and mag will come down on their own.

 

Plus, next time use instant ocean -not reef crystal - less calcium.

[Origami]

I'd just let consumption pull it back down. The calcium numbers are high, but it'll come down naturally with time. The other two parameters, I'm far less concerned with.

[Curtis Scott]

I'd just let consumption pull it back down. The calcium numbers are high, but it'll come down naturally with time. The other two parameters, I'm far less concerned with.

 

Reassuring to hear, thanks Tom.

 

Btw, do we have a thread where we can find out more info on the FragFest on the 26th? I noticed the current link goes to the winter meeting thread.

Edited August 16, 2012 by Curtis Scott

[flowerseller]

In a case like this, water changes will dilute these numbers only a slight bit because you are still adding back at normal levels with the new sea water. I'd also simply monitor the levels, like others have suggested, and only do a water exchange if it falls into your normal water change routine. A better example of a water change that would hold a major benifit would be to dilute, say elevated levels of ammonia, nitrite or nitrate or the like.

Just a question,

have you changed anything as far as residents go that may have caused your levels to increase or is it simply a function of misadjustment via dosing?

This is meant to ask if you have removed any large consumers or your frags growth has simply peaked and leveled off for the time being?

[Curtis Scott]

have you changed anything as far as residents go that may have caused your levels to increase or is it simply a function of misadjustment via dosing?

 

Only thing I can think of is... I did have about 30 frags of SPS that were doing great when levels were within normal for a bout 5 weeks while they encrusted to the plugs, once those were sold I was foolishly not monitoring my Calcium thinking it was inline using the dosing pump. It is a week past do for a WC so I plan to do a 30g one tonight after this it is back to waiting and monitoring. I think it was just a case of over dosing, possibly combined with the removal of those calcium absorbing frags.

Edited August 17, 2012 by Curtis Scott

[taiscici]

I used to have the same problem. I raised my ALK to 11-12 dkh and calcium starts to come down. Good Luck!

[flowerseller]

If you removed 30 calcium depleting corals and did not reduce your input, it might be the problem.

Follow the advise from several others and let it drop naturally.

 

@ taiscici, if you simply raised your alk level, I'm not following you on how that reduced your Ca level?

[Origami]

I used to have the same problem. I raised my ALK to 11-12 dkh and calcium starts to come down. Good Luck!

That's one way to do it. Add enough alkalinity that your high calcium levels begin to precipitate out. I'd rather just let the level drift down while supplementing alkalinity as needed until balance is achieved. It may take a little time, but if nothing's complaining now, then nature will take care of things.

 

Link to next meeting:

http://www.wamas.org/forums/topic/51302-summer-frag-fest-extravaganza/

[flowerseller]

That's one way to do it. Add enough alkalinity that your high calcium levels begin to precipitate out. I'd rather just let the level drift down while supplementing alkalinity as needed until balance is achieved. It may take a little time, but if nothing's complaining now, then nature will take care of things.

 

I was afraid that was the thinking but 11-12 isn't going to do it. Plus, for almost anyone, this wil be the first hill of a long roller coaster that is going to give you way more ride than your stomach will likely be willing to handle. I found 15+ is needed to get the ride going and been real hard to stop it once it gets to going. You can tell when it's going to move by the tips of sps.

 

Not that I'm a tree hugger but in this case al natural is the leaf of choice.

Unless of course you simply drain the tank empty and refill it with correct sea water as anything before that is just diluting which is why small water changes are not effective in this scenario.

[Origami]

^^ Probably needed to be clearer. I was speaking tongue in cheek about boosting the alk to precipitation levels. That's like dynamiting your house to get rid of mice in this case. You've got a high magnesium level that will impede precipitation and you would, indeed, have to push the alk up to uncomfortable levels. Don't boost the alk to force calcium out through precipitation. You can do water changes or just let nature run it down. If the latter, just watch your alkalinity and dose to keep it where you want it. Let the others drift back through consumption.

[Curtis Scott]

UPDATE:

I checked the tank parameters last night and the Calcium is now at ~550ppm (finally starting to come down!) and the Alkalinity is 8.2dkh. I am dosing the Alkalinity to try to get it back up to 9dkh, and not dosing any Calcium for the time being until it gets back down to around 450. Thank you guys for all the advice, it was very much appreciated.