I am in the process of setting up my first tank and i'm having trouble with my apex salinity probe. The salinity probe itself is fairly old about 3 years old but it was never opened or used as I had my apex on a freshwater tank. I opened it up and calibrated it in my new tank and initially it seemed fine. It read 35 ppt and agreed with my refactometer.
However over the past 3 weeks it keeps dropping lower and lower and lower. I haven't done any water changes, just ATO as my tank gets established. Refractometer still reads 35 ppt. Below is what it looks like over a week, its currently down to about 23.
Any idea what is causing this or how to fix it?
However over the past 3 weeks it keeps dropping lower and lower and lower. I haven't done any water changes, just ATO as my tank gets established. Refractometer still reads 35 ppt. Below is what it looks like over a week, its currently down to about 23.
Any idea what is causing this or how to fix it?