Can't seem to lower Calcium & Mag

[Austin Lee]

Hi all,

I have a 25 lagoon with a couple acans, a hammer, a zoa, a monti, and a ricordea florida. I've been struggling with low alkalinity and high Mag & calcium. I was at WWC the other day and they recommended I use Brightwell 8.3 to raise my alkalinity without raising my calcium.

Here are my test results before dosing (7/18):
Alk: 8.9 (Hanna)
Calc: 546 (Hanna)
Mag: 1500+ (unmeasurable - Salifert)

I dosed the buffer on 7/20

Here they are after (7/22):
Alk: 9.7
Calc: 541
Mag: 1500+ (still unmeasurable)

The calc has been around this number for a while (over 500 since 7/4), and the mag has only recently been high (since 7/18).

I'm still new to learning how these three elements work together other than knowing that to lower calcium you should raise alk, etc. I know it's only been a couple of days, so should I just test a few times a week for a couple of weeks to see if this changes? I know these numbers aren't detrimental to my corals, and everything looks happy other than my monti's polyps not extending.

Any help would be appreciated

 

[P-Dub]

Just maintain your Alk as it gets depleted and do not add Ca or Mg. Let those get consumed by your organisms until all elements come in balance. At that point dose at a rate to match consumption. That is what I would do but others might be better equipped to help such as this great read by our very own @Randy Holmes-Farley...

Chemistry And The Aquarium: Solving Calcium And Alkalinity Problems

I hope this article proves useful is understanding and dealing with the different types of calcium and alkalinity problems encountered by reef keepers. Once you get calcium and alkalinity under control, you are far along the road to having your tank chemistry optimal for its inhabitants.

www.advancedaquarist.com

 

[Austin Lee]

Bump

 

[BeejReef]

+1 to P-Dub and to what WWC advised.

see https://www.advancedaquarist.com/2002/11/chemistry

You're a "zone 4."

Calcium and magnesium will appear to fall back into the "acceptable" range a lot slower than your alkalinity falls just bc there is a lot more of both of those elements in a given volume of seawater. You'll probably have to re-dose your alkalinity up for a week or three before you're able to really see the progress in your testing.

 

[lapin]

Hi all,

I have a 25 lagoon with a couple acans, a hammer, a zoa, a monti, and a ricordea florida. I've been struggling with low alkalinity and high Mag & calcium. I was at WWC the other day and they recommended I use Brightwell 8.3 to raise my alkalinity without raising my calcium.

Here are my test results before dosing (7/18):
Alk: 8.9 (Hanna)
Calc: 546 (Hanna)
Mag: 1500+ (unmeasurable - Salifert)

I dosed the buffer on 7/20

Here they are after (7/22):
Alk: 9.7
Calc: 541
Mag: 1500+ (still unmeasurable)

The calc has been around this number for a while (over 500 since 7/4), and the mag has only recently been high (since 7/18).

I'm still new to learning how these three elements work together other than knowing that to lower calcium you should raise alk, etc. I know it's only been a couple of days, so should I just test a few times a week for a couple of weeks to see if this changes? I know these numbers aren't detrimental to my corals, and everything looks happy other than my monti's polyps not extending.

Any help would be appreciated

Because inquiring minds want to know; How did your mag and cal get so high?

 

[Austin Lee]

Thank you both!!!

 

[Austin Lee]

Because inquiring minds want to know; How did your mag and cal get so high?

I don’t know, honestly. I think I just don’t have a lot of consumption. I only dose for alkalinity (as mentioned in my post).

Here are the only things I put in my tank:
- Reef Crystals salt
- Reef Roids (on occasion)
- LRS Nano Frenzy food

No other additives.

 

[BeejReef]

if you have never dosed calcium or magnesium before, then you need to suspect either your test kits or a bad batch of salt

 

[Calpoly2103]

It sounds like something is up with either your test kits or your batch of salt. I would take some water and go to LFS to ask them to test it. Or you can go buy some additional test kits to double check your results.

When I first started the first Salifert Big 3 (Alk/Mag/Cal) I bought the kits were bad. I was testing 550 / 1600 / 13. I complained and got another shipment which then read normal levels.

 

[Austin Lee]

if you have never dosed calcium or magnesium before, then you need to suspect either your test kits or a bad batch of salt

Can't remember if this is my 1st or 2nd batch of salt with these results. Going to start adding that as a note on my test results spreadsheet!

Could very well be a bad kit, though. I'm using Hanna for Calcium and haven't heard good things about it's accuracy. Going to continue to monitor.

 

[Austin Lee]

It sounds like something is up with either your test kits or your batch of salt. I would take some water and go to LFS to ask them to test it. Or you can go buy some additional test kits to double check your results.

When I first started the first Salifert Big 3 (Alk/Mag/Cal) I bought the kits were bad. I was testing 550 / 1600 / 13. I complained and got another shipment which then read normal levels.

Good call. Going to do that this weekend. Using Hanna for Calcium and Salifert for Mag. Mag seems to have been more accurate as I was getting lower results a couple of weeks back - it hasn't been consistently high. Not the case for Hanna on the other hand. Lowest it registered was 471.

 

[P-Dub]

Good call. Going to do that this weekend. Using Hanna for Calcium and Salifert for Mag. Mag seems to have been more accurate as I was getting lower results a couple of weeks back - it hasn't been consistently high. Not the case for Hanna on the other hand. Lowest it registered was 471.

I find the red sea test kit for calcium accurate and easy enough to perform. Alk on my Hanna is within .3 of what the Red Sea reads, FWIW.

 

[Matthew Russell]

It sounds like something is up with either your test kits or your batch of salt. I would take some water and go to LFS to ask them to test it. Or you can go buy some additional test kits to double check your results.

When I first started the first Salifert Big 3 (Alk/Mag/Cal) I bought the kits were bad. I was testing 550 / 1600 / 13. I complained and got another shipment which then read normal levels.

I was going to say the same thing. I just had a similar experience. I was getting high readings on my magnesium so I read the directions again for the Red Sea test kit then did a slow methodical test and found my magnesium was in an acceptable range. I must have just been rushing. As far as the Hanna kits go; make sure they’re clean, rinse with RO, and you can buy calibration solutions that come in handy when in doubt.