Help!, salinity too high

[TCOTU]

I have a relatively mature 100G tank with mixed reef with soft corals and few montipora and torch corals. I have tested my water chemistry weekly. I have automatic water change with clean saltwater made with RODI and Tropic Marin salt. I dose two part BRS CaCl and soda ash, plus BRS two part maintenance magnesium mix. About 2 to 3 months ago, the salinity started to rise, to about 1.027. (I calibrate the refractometer monthly). It stayed there for a while, all animals in the tank seem to be doing well. then 2 weeks ago, salinity suddenly shot up to 1.030. (Ca448, Alk 9.52) Again, the livestock seems ok. I thought it was a fluke, and because the fish and corals seem ok, and I was busy with work, I didn't recheck it again. Last week, I did my weekly water test and salinity was above 1.030! And one of the fish died. I removed about 10 G of tank water over 2 days and let ATO refill it with RODI water. I also stopped all dosing. Salinity came down to 1.027. I tried to figure out where the extra salt came from. The newly made salt water tested fine, in fact it was a little low at 1.024. Water test also shows low Ca (417) and Alk (6.83), obviously. It was So I restarted dosing Ca and Alk, not Mag. One day later, the salinity is starting to go up again, to 1.028. It seems dosing Ca and Alk raising the salinity significantly.

Looking online, I see no discussion of this. One of the articles by Mr Holms did mention that two part dosing can cause salinity to creep up over time, like over a year. This is happening over 24 hours. Am I missing something? If I made a bad batch of CaCl or Soda Ash, how do I test them?

 

[TCOTU]

I have a relatively mature 100G tank with mixed reef with soft corals and few montipora and torch corals. I have tested my water chemistry weekly. I have automatic water change with clean saltwater made with RODI and Tropic Marin salt. I dose two part BRS CaCl and soda ash, plus BRS two part maintenance magnesium mix. About 2 to 3 months ago, the salinity started to rise, to about 1.027. (I calibrate the refractometer monthly). It stayed there for a while, all animals in the tank seem to be doing well. then 2 weeks ago, salinity suddenly shot up to 1.030. (Ca448, Alk 9.52) Again, the livestock seems ok. I thought it was a fluke, and because the fish and corals seem ok, and I was busy with work, I didn't recheck it again. Last week, I did my weekly water test and salinity was above 1.030! And one of the fish died. I removed about 10 G of tank water over 2 days and let ATO refill it with RODI water. I also stopped all dosing. Salinity came down to 1.027. I tried to figure out where the extra salt came from. The newly made salt water tested fine, in fact it was a little low at 1.024. Water test also shows low Ca (417) and Alk (6.83), obviously. It was So I restarted dosing Ca and Alk, not Mag. One day later, the salinity is starting to go up again, to 1.028. It seems dosing Ca and Alk raising the salinity significantly.

Looking online, I see no discussion of this. One of the articles by Mr Holms did mention that two part dosing can cause salinity to creep up over time, like over a year. This is happening over 24 hours. Am I missing something? If I made a bad batch of CaCl or Soda Ash, how do I test them?

Sorry, Mr Holms-Farley.

 

[Malum Argenteum]

I have automatic water change

This is where I'd start troubleshooting. Overfilling at the time of water change will cause salinity to rise.

 

[Lavey29]

Perhaps you should get a second salinity test at your LFS to confirm. My salinity slowly rises over time as well and is corrected during water changes.

 

[Randy Holmes-Farley]

I have a relatively mature 100G tank with mixed reef with soft corals and few montipora and torch corals. I have tested my water chemistry weekly. I have automatic water change with clean saltwater made with RODI and Tropic Marin salt. I dose two part BRS CaCl and soda ash, plus BRS two part maintenance magnesium mix. About 2 to 3 months ago, the salinity started to rise, to about 1.027. (I calibrate the refractometer monthly). It stayed there for a while, all animals in the tank seem to be doing well. then 2 weeks ago, salinity suddenly shot up to 1.030. (Ca448, Alk 9.52) Again, the livestock seems ok. I thought it was a fluke, and because the fish and corals seem ok, and I was busy with work, I didn't recheck it again. Last week, I did my weekly water test and salinity was above 1.030! And one of the fish died. I removed about 10 G of tank water over 2 days and let ATO refill it with RODI water. I also stopped all dosing. Salinity came down to 1.027. I tried to figure out where the extra salt came from. The newly made salt water tested fine, in fact it was a little low at 1.024. Water test also shows low Ca (417) and Alk (6.83), obviously. It was So I restarted dosing Ca and Alk, not Mag. One day later, the salinity is starting to go up again, to 1.028. It seems dosing Ca and Alk raising the salinity significantly.

Looking online, I see no discussion of this. One of the articles by Mr Holms did mention that two part dosing can cause salinity to creep up over time, like over a year. This is happening over 24 hours. Am I missing something? If I made a bad batch of CaCl or Soda Ash, how do I test them?

Over a year the rise is very large. Over a week it is not.

 

[TCOTU]

Over a year the rise is very large. Over a week it is not.

Thanks for the reply. I have stopped dosing Ca, only Soda Ash for now. I am thinking if this experiment will work. Let's say I start with 1 L or 1 G of RODI water, presumably salinity should be 1.000. If I add 1 ml of my BRS CaCl mix, and 1 ml of Alkalinity (BRS soda ash mix), how much should I expect the salinity to rise? I am not enough of a chemist to figure this out.

 

[Randy Holmes-Farley]

Thanks for the reply. I have stopped dosing Ca, only Soda Ash for now. I am thinking if this experiment will work. Let's say I start with 1 L or 1 G of RODI water, presumably salinity should be 1.000. If I add 1 ml of my BRS CaCl mix, and 1 ml of Alkalinity (BRS soda ash mix), how much should I expect the salinity to rise? I am not enough of a chemist to figure this out.

Why would you do that? It is easier and
more accurate to calculate than do the experiment. I gave calculated data in the article you daw.

 

[Randy Holmes-Farley]

After 1 year of adding 8 ppm of calcium and the accompanying 1.1 dKH of alkalinity per day, there is roughly a 29% rise in salinity over a year when not doing water changes).

 

[Jamie814]

I have automatic water change with clean saltwater made with RODI and Tropic Marin salt.

This could also be your issue. How certain are you that your auto water change is removing the EXACT same amount of saltwater as it is putting back in? If it is adding slightly more than it is taking out your salinity will rise overtime.

 

[TCOTU]

Why would you do that? It is easier and
more accurate to calculate than do the experiment. I gave calculated data in the article you daw.

The only reason to do this would be to see if the batch I made was bad or wrong. I think adding the two parts raised the salinity faster than expected. Yet I don't know a why to test that, other than throw it out and make another one.

 

[TCOTU]

This could also be your issue. How certain are you that your auto water change is removing the EXACT same amount of saltwater as it is putting back in? If it is adding slightly more than it is taking out your salinity will rise overtime.

I use Neptune DOS to remove and add exact same amount at the same time. It is 4 L (for a 100 G tank) over 24 hours, divided by the DOS automatically into equal parts every 12 minutes. I have not calibrated the DOS per se, but if it was adding more salt water than removing old water, I think it would raise it slowly over time, and maybe even overflow the tank before raising the salinity noticeably.

 

[Jamie814]

I use Neptune DOS to remove and add exact same amount at the same time. It is 4 L (for a 100 G tank) over 24 hours, divided by the DOS automatically into equal parts every 12 minutes. I have not calibrated the DOS per se, but if it was adding more salt water than removing old water, I think it would raise it slowly over time, and maybe even overflow the tank before raising the salinity noticeably.

I would calibrate the DOS by verifying that it is removing and adding the correct amounts. Use two 1 gallon jugs and see if they both empty and fill the same amount at the same time.

This would eliminate the water change as your potential issue.

 

[SquidwardTentacles05]

I have a relatively mature 100G tank with mixed reef with soft corals and few montipora and torch corals. I have tested my water chemistry weekly. I have automatic water change with clean saltwater made with RODI and Tropic Marin salt. I dose two part BRS CaCl and soda ash, plus BRS two part maintenance magnesium mix. About 2 to 3 months ago, the salinity started to rise, to about 1.027. (I calibrate the refractometer monthly). It stayed there for a while, all animals in the tank seem to be doing well. then 2 weeks ago, salinity suddenly shot up to 1.030. (Ca448, Alk 9.52) Again, the livestock seems ok. I thought it was a fluke, and because the fish and corals seem ok, and I was busy with work, I didn't recheck it again. Last week, I did my weekly water test and salinity was above 1.030! And one of the fish died. I removed about 10 G of tank water over 2 days and let ATO refill it with RODI water. I also stopped all dosing. Salinity came down to 1.027. I tried to figure out where the extra salt came from. The newly made salt water tested fine, in fact it was a little low at 1.024. Water test also shows low Ca (417) and Alk (6.83), obviously. It was So I restarted dosing Ca and Alk, not Mag. One day later, the salinity is starting to go up again, to 1.028. It seems dosing Ca and Alk raising the salinity significantly.

Looking online, I see no discussion of this. One of the articles by Mr Holms did mention that two part dosing can cause salinity to creep up over time, like over a year. This is happening over 24 hours. Am I missing something? If I made a bad batch of CaCl or Soda Ash, how do I test them?

You should bring it down, by adding a little fresh water to ur tank every day.

 

[Randy Holmes-Farley]

The only reason to do this would be to see if the batch I made was bad or wrong. I think adding the two parts raised the salinity faster than expected. Yet I don't know a why to test that, other than throw it out and make another one.

No, that is not it. Two parts cannot be made much more potent than the recipes due to solubility limitations.

Testing a salinity boost is an extremely poor way to test a two part. Looking for the expected alk boost would be one good way.

 

[Malum Argenteum]

I reread the first post, and another thing that comes to mind is testing error. I would double check the salinity measurements with a different device -- a Tropic Marin hydrometer would be my choice. I personally find refractometers not as foolproof as I'd like.

The fact that your new SW was so far off is something else to look into -- another testing error, or some other glitch in the procedure.

 

[TCOTU]

I would calibrate the DOS by verifying that it is removing and adding the correct amounts. Use two 1 gallon jugs and see if they both empty and fill the same amount at the same time.

This would eliminate the water change as your potential issue.

Thanks. I will re-calibrate DOS and eliminate that as a potential cause.

 

[TCOTU]

No, that is not it. Two parts cannot be made much more potent than the recipes due to solubility limitations.

Testing a salinity boost is an extremely poor way to test a two part. Looking for the expected alk boost would be one good way.

That is good to know. Do you think it would wreck the whole system if I dose alkalinity only for a while? I am trying to add one items at a time and see how things change. I know both Ca and Alk are linked and need to be in balance, I am just not sure if I tinker with one, what happens with the other. So far pH is holding steady at 8.3.

 

[TCOTU]

I reread the first post, and another thing that comes to mind is testing error. I would double check the salinity measurements with a different device -- a Tropic Marin hydrometer would be my choice. I personally find refractometers not as foolproof as I'd like.

The fact that your new SW was so far off is something else to look into -- another testing error, or some other glitch in the procedure.

I have thought of that as well. But correct me if wrong, I thought the refractometer is a simple device that is unlikely to break. I did use calibration fluid and it reads correctly at 35. If I introduce a second method and it gives a different reading, how am I certain that the second device is correct? One almost have to use a third method, perhaps only to find out that the original refractometer is correct.

 

[fish_collector]

That is good to know. Do you think it would wreck the whole system if I dose alkalinity only for a while? I am trying to add one items at a time and see how things change. I know both Ca and Alk are linked and need to be in balance, I am just not sure if I tinker with one, what happens with the other. So far pH is holding steady at 8.3.

Yes adding only soda ash is a bad idea. Why would you do that?
It would be wiser to stop your automatic water changer and verify the ATO is working correctly first.
Are you certain your ATO isn't adding salt water instead of rodi? Hey just asking.

 

[Malum Argenteum]

I have thought of that as well. But correct me if wrong, I thought the refractometer is a simple device that is unlikely to break. I did use calibration fluid and it reads correctly at 35. If I introduce a second method and it gives a different reading, how am I certain that the second device is correct? One almost have to use a third method, perhaps only to find out that the original refractometer is correct.

I personally had serious problems with my last refractometer. The quality of the thing was questionable, and it was old, and I don't think it held a calibration well. My calibration fluid was off, which I did not know. And I find them a bit hard to read, in terms of precision. Much of this -- less than perfect eyesight, bought a cheap refractometer, didn't take pains to make sure my calibration was on point -- was my fault, of course, and I'm not offloading blame onto an inert object.

You're right that there's something of a rabbit hole that one can fall into with salinity/SG measurements. But once a person has run themselves silly trying to track down some problem only to find out it was mostly a testing error, spending some time in a hole doesn't look so bad. My 2 cents, anyway.