Losing salinity

[Kathy Floyd]

My tank is still in the cycling process, however, today when I checked the salinity it was 1.20. It started at 1.25. I have an ATO set up but am curious why the salinity is dropping. I know there is a lot of evaporation but why is the salinity dropping?

 

[Jay Hemdal]

Interesting conundrum - evaporation only loses pure H2O, the salts remain behind. Somewhere, you must be losing seawater from the system and it is being replaced with freshwater.

The only other way to account for this would be some error in your measurement method. Here is an article about that:

Measuring Salinity / Specific Gravity in Aquariums

This article gives an overview of measuring specific gravity / salinity in aquariums.

www.reef2reef.com

Jay

 

[Kathy Floyd]

Interesting conundrum - evaporation only loses pure H2O, the salts remain behind. Somewhere, you must be losing seawater from the system and it is being replaced with freshwater.

The only other way to account for this would be some error in your measurement method. Here is an article about that:

Measuring Salinity / Specific Gravity in Aquariums

This article gives an overview of measuring specific gravity / salinity in aquariums.

www.reef2reef.com

Jay

Hi Jay,

I use a refractometer. It was calibrated and when I measured my current tank, I was spot on. Then I measured the cycling tank and got 1.20. I am going to keep an eye on it because to be totally honest, I went by what the fish store told me their salinity was and never checked it myself first.

 

[V A R I A N T]

Do you have a skimmer and is it producing overly wet? Temperature affecting SG? ATO put too much water in because of an open sensor?

 

[Kathy Floyd]

Do you have a skimmer and is it producing overly wet? Temperature affecting SG?

I do not have a skimmer running on the cycling tank. Temperature has been steady around 79.

**edit, I did have a skimmer running for a few days, but did shut it off. Maybe it did cause that issue?

 

[Cichlid Dad]

Hi Jay,

I use a refractometer. It was calibrated and when I measured my current tank, I was spot on. Then I measured the cycling tank and got 1.20. I am going to keep an eye on it because to be totally honest, I went by what the fish store told me their salinity was and never checked it myself first.

Hello, I recently had an issue with lfs water myself. It's one that has been around forever. I picked up 25 gallons of salt water and in the past never tested water from them. This time I did. I was going to match my new water to my tank parameters. Tested out it was 350 cal, 5.3 alk 750 mag but 1.025 I don't remember pH. I tested twice then tested my tank and my tank was on par. Talked with the owner, he kinda blew me off. I now am ordering my ordi unit.

 

[V A R I A N T]

A skimmer can deplete salt from the water column when wet skimming. You would know because of the excess of water/skimmate collecting in the cup or container. I doubt the skimmer alone would cause this drop in SG if it was ran for a limited time. Have you performed any water changes? It appears the refractometer could be the culprit if no other factors can be found.

 

[exnisstech]

Hi Jay,

I use a refractometer. It was calibrated and when I measured my current tank, I was spot on. Then I measured the cycling tank and got 1.20. I am going to keep an eye on it because to be totally honest, I went by what the fish store told me their salinity was and never checked it myself first.

Are you saying you got the water from the LFS that is in the tank that is testing at
1. 020? And you did not test that water when you got it? At least that's how I'm reading it. If so maybe they were wrong and it was 1.020 all along? Skimmer removing and ato adding is about the only way I can think of salinity lowering.

 

[Kathy Floyd]

Are you saying you got the water from the LFS that is in the tank that is testing at
1. 020? And you did not test that water when you got it? At least that's how I'm reading it. If so maybe they were wrong and it was 1.020 all along? Skimmer removing and ato adding is about the only way I can think of salinity lowering.

Yes and I know, a rookie mistake. The skimmer is off. I added some sw to increase the level and will monitor it to see if it levels off and stays that way.

 

[exnisstech]

Yes and I know, a rookie mistake. The skimmer is off. I added some sw to increase the level and will monitor it to see if it levels off and stays that way.

You use salt water to top off and raise it slowly that way.