Cal and Alk weirdly high without dosing

Breef320

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Hello,

It’s been a while since I’ve posted but been reading fairly regularly.

We went on vacation and came back to a mad tank. All of our fears, right?

I did my weekly w/c that night and swapped 20% rather than my normal 10%. Moving on to this week. The tank still looks pretty sad. No surprises there as I am trying not to over-react. I’ve seen poor PE, acans retracted and even some white skeleton showing, monti digi about half gone, white skeleton showing on Hollywood stunner, lost a head of hammer…etc.
I tested today and found that my calcium and alkalinity were high (relative to where I keep them typically) although I don’t dose and rely on water changes for supplement.
I normally am 8dkh and 430 ppm cal but today I tested 10.7dkh and 500 ppm cal. Salinity still 1.026.
This absolutely baffled me because I’ve been incredibly stable around 8-8.5 on my alk let alone the wild cal reading. I even tested 3 times to verify.

My first thought was the NSW mix so I mixed up a new 1.026 salinity batch and tested it and it came right in at 8.5dkh and 440ppm cal. This is from the same pail I’ve been using for months. Red Sea blue bucket is my go to.

I run a pretty low nutrient system at 10pm NO3 and 0.01ppm PO4 as of this mornings test which are I line with previous readings.

Where in the world could the excess cal and alk have come from?

Ideas?
 

Garf

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Hello,

It’s been a while since I’ve posted but been reading fairly regularly.

We went on vacation and came back to a mad tank. All of our fears, right?

I did my weekly w/c that night and swapped 20% rather than my normal 10%. Moving on to this week. The tank still looks pretty sad. No surprises there as I am trying not to over-react. I’ve seen poor PE, acans retracted and even some white skeleton showing, monti digi about half gone, white skeleton showing on Hollywood stunner, lost a head of hammer…etc.
I tested today and found that my calcium and alkalinity were high (relative to where I keep them typically) although I don’t dose and rely on water changes for supplement.
I normally am 8dkh and 430 ppm cal but today I tested 10.7dkh and 500 ppm cal. Salinity still 1.026.
This absolutely baffled me because I’ve been incredibly stable around 8-8.5 on my alk let alone the wild cal reading. I even tested 3 times to verify.

My first thought was the NSW mix so I mixed up a new 1.026 salinity batch and tested it and it came right in at 8.5dkh and 440ppm cal. This is from the same pail I’ve been using for months. Red Sea blue bucket is my go to.

I run a pretty low nutrient system at 10pm NO3 and 0.01ppm PO4 as of this mornings test which are I line with previous readings.

Where in the world could the excess cal and alk have come from?

Ideas?
How are you calibrating your salinity measuring device?
 

Featherweight

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Tagging along. Recently had a similar issue occuring. I think I've stabilized, but it was a bizarre shift in the ALK trend of my system
 
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Breef320

Breef320

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Are you dosing any nitrate or phosphate?
I am not but the person feeding my tank did slightly over feed but I didn’t see an increase in the tests when I got back from vacation.

All i had them do is feed. And asked them not to reach in the tank. I did ask if they did anything else and they said no.

How are you measuring salinity? If it elevates so will alk. Also magnesium is the buffer for alk and calcium have you checked that number?
I just hopped off the couch and checked. RSCP test showed 1460
 

Garf

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I am not but the person feeding my tank did slightly over feed but I didn’t see an increase in the tests when I got back from vacation.

All i had them do is feed. And asked them not to reach in the tank. I did ask if they did anything else and they said no.


I just hopped off the couch and checked. RSCP test showed 1460
I don't suppose you have added a "pH buffer" or anything to increase pH? Even if it sais on the bottle/box that it doesn't impact Alkalinity.
 
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Breef320

Breef320

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I don't suppose you have added a "pH buffer" or anything to increase pH? Even if it sais on the bottle/box that it doesn't impact Alkalinity.
Nope!

I did notice that some of the coraline on the back glass is now gone. Will that dissipate back into the water column? It wasn’t even that much
 

Garf

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Nope!

I did notice that some of the coraline on the back glass is now gone. Will that dissipate back into the water column? It wasn’t even that much
What test are you using for Alk? If it's Salifert, I've seen folk using 5ml samples instead of 4, and peeps reading the chart upside down, ie. the Alk is actually getting lower, not higher. I don't have any experience with any other Alk test apart from one involving a pH probe.
 

Randy Holmes-Farley

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Nope!

I did notice that some of the coraline on the back glass is now gone. Will that dissipate back into the water column? It wasn’t even that much

No, there won’t be much dissolution of old coralline. Some dissolution of rock and sand can take place, and is normal. But not typically as much as you note.

No in tank chemistry can explain the calcium rise. It’s either test error, a salinity rise, or from the water changes if the mix was very high.
 
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Breef320

Breef320

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What test are you using for Alk? If it's Salifert, I've seen folk using 5ml samples instead of 4, and peeps reading the chart upside down, ie. the Alk is actually getting lower, not higher. I don't have any experience with any other Alk test apart from one involving a pH probe.
I’m am indeed using Salifert. I’ll search the forums on this.
Are they intentionally using 5ml of aquarium water?

I’m cheating on the math, I just typed the “remaining solution” into the Neptune fusion and it did the math but I just checked the chart in the manual. The plunger was on the 0.31 line. Which converted correctly.

No, there won’t be much dissolution of old coralline. Some dissolution of rock and sand can take place, and is normal. But not typically as much as you note.

No in tank chemistry can explain the calcium rise. It’s either test error, a salinity rise, or from the water changes if the mix was very high.
Thank you Randy, I’m with ya. It’s gotta be a human error that I didn’t realize I did and don’t know what it would have been.

I guess I get to pick up the pieces from the mistake and be more careful.

I gotta get a bigger tank… this nano just isn’t for me. I’m just not anal enough and it seems any little thing throws the tank in a tizzy.
 

njmaddreefer

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I've had poor success measuring my salinity with the refractometers in the past. Even when I calibrated it with the BRS solution I still managed to interpret the line incorrectly.

Keep us posted I'm super curious what it could be. Have you tried getting a second opinion from your LFS yet?
 

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