Salinity Level decreasing during Tank cycle

Kaushik5916

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Hi,
It’s been about 18 days I’ve left my New Nano 19L Tank for cycling. This is my first Salt water Aquarium (Setting it up for Clown fishes :))

I recently checked my Salinity levels and noticed it had dropped (Look at the Image for reference) Btw I’m using a Float Hydrometer for testing Salinity.

As far as I’ve gathered information, the Salinity levels increase due to Evaporation, but in my case it’s decreasing. The water is getting evaporated and the water level is going down and so is the Salinity level.

Firstly, is that normal?

If not, what am I to do to increase my Salinity levels to the right level of 1.024 or so?

Thanks in Advance :)

IMG_1127.jpeg
 
Is the water level moving at all? Personally I would question the testing device. I'm not familiar with that tester, I suggest refractometers or hanna, I like the hanna digital tester.
 
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Its also strongly advised that every tank should have an auto top off (ATO) to prevent salinity swings, its one of the best $100 you can spend on your tank.
 
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Yes, the overall water level did come down due to Evaporation.

Thanks :)
So salinity should go up, that leads me to believe it is a test error.
True that, the Hydrometer gave me the same reading few weeks back as well, when I tested. Probably will get a new one and test it again :) Thank you so much for your time.
 
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Water temperature change will change the reading on hydrometers.
I’ve got an Aqua one heater that is set to 26 deg Celsius. And the Hydrometer has a Thermometer that shows the Temperature to be Approx 22-24 deg Celsius.

Could you please tell me how the water temperature has something to do with the Salinity levels? Thanks :)
 
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I’ve got an Aqua one heater that is set to 26 deg Celsius. And the Hydrometer has a Thermometer that shows the Temperature to be Approx 22-24 deg Celsius.

Could you please tell me how the water temperature has something to do with the Salinity levels? Thanks :)
Water temp affects hydrometer accuracy because water density changes with temperature. It becomes less dense as it warms and causes the hydrometer to sink deeper.

My guess is this is what’s happening as I don’t think it’s possible for salinity to drop without physically removing salt from the water, or adding water with no salt.
 
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Water expands or contracts with temperature which alters its density. Your salinity measuring device measures the density of water, how high it floats is dependent on the water density.
It was calibrated at a specific temperature, or range.
It might have temp compensation tables in the manual.
 
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I’ve got an Aqua one heater that is set to 26 deg Celsius. And the Hydrometer has a Thermometer that shows the Temperature to be Approx 22-24 deg Celsius.

Could you please tell me how the water temperature has something to do with the Salinity levels? Thanks :)
Water temp affects hydrometer accuracy because water density changes with temperature. It becomes less dense as it warms and causes the hydrometer to sink deeper.

My guess is this is what’s happening as I don’t think it’s possible for salinity to drop without physically removing salt from the water, or adding water with no salt.
Well, that makes sense. Thanks :) So am I to try the test again with the heater off? Or any suggestions on what am I to do next?
 
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Water expands or contracts with temperature which alters its density. Your salinity measuring device measures the density of water, how high it floats is dependent on the water density.
It was calibrated at a specific temperature, or range.
It might have temp compensation tables in the manual.
Alright, get it. Thanks heaps for all that knowledge :) Appreciate it.
 
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