Low salinity

Roger30

Premium Member
I have a AIO rimless 30 gallon that has up and running for 9 months now. My goal is to get keep my salinity at around 1.025. However for the last few months my salinity has been around 1.023. I buy my water and do a 50% water change every other week. I tested the water I purchase and it's salinity is 1.025. I have ato system with a 5 gallon reservoir that last me 15+ days. Any ideas why my salinity level keeps dropping?
 

Roger30

Premium Member
I use a hydrometer. I am running a skimmer. I guess that could be it. How do I keep my salinity up?
 

Roger30

Premium Member
To keep my ca and alk levels high and nitrates low? Avoid dosing until I am more experience. Should I do less of a water change?
 

grant778

New member
Its probably what Randy Holmes-Farley said thats lowering ur salinity. I try to keep my tank at 1.024. If I do a water change every other week my salinity goes to around 1.0235, if I do a water change every week, like I do now, the drop in salinity due to the skimmate being replaced with fresh water is minimal since the minor drop in salinity is corrected during my water change every week.
 

Randy Holmes-Farley

Reef Chemist
Premium Member
When you empty the skimmer cup, you can just add about that amount of salt water to prevent salinity loss. :)

The explanation may also just be salinity error. Hydrometers can easily vary a bit day to day unless it is a high quality glass floating hydrometer. ;)
 
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