salinity drops

[Brandon Lovato]

i was wondering does salinity drop as more top off water is added?

this is my problem i add about 5 gallons of water top off a day that is all kalk top off set up through a drip system.
i have a bout 350 totall gallons of water and do water changes once a month.
it seems to me that my salinity falls i try to keep it at about 1.024 or 1.025 and as the month moves a long the salanity falls to about 1.022 i find my self dumping in 4 or 5 cups of salt during this month to bring it back up.
does this happen all the time i always thought salinity always stayed at the same level and this did not evaporate with the water.
i use instant ocean salt

just wanted to know if this is normal.
brandon

 

[Randy Holmes-Farley]

i was wondering does salinity drop as more top off water is added?


Only if it is replacing salt water that was removed (say, by skimming). If it is replacing evaporated water, it will not reduce salinity in the long run. Of course, it reduces it a tiny bit each time you add it, but the tank gets a little higher in salinity due to evaporation, until you add it again.

 

[Brandon Lovato]

so why does my salinity drop over time i do not over skimm by no means i probably under skimm i have no idea why it drops.

 

[Randy Holmes-Farley]

I do not know.

How are you measuring salinity?

Is the water level exactly constant?
Does the water change water match the tank in salinity?