Salinity issues

[iamahab]

I have two nano tanks (waterbox mini 15 , evo 13.5) Both have open tops and evaporation issues.I have a fz ATO but I'm confused about it's usefulness. In order for the sensor to register that the water level has dropped i'd have to lose enough water to make my salinity rise more than I think is safe. Am I better off just topping off with fresh ro water manually each day or maybe twice a day? I've read that even a slight change in salinity will negatively effect corals and the general health of the tank?

 

[Reef.]

That’s what I do, manually top off twice a day, far more stable.

My reason was floss would slow the flow enough to trigger the ato, the reason you state tho shouldn’t be an issue with just normal evaporation, the salinity shouldn’t move that much, could be a combination of evaporation and maybe reduced flow triggering the ato.

But yeah manual is definitely an option.

 

[Pistondog]

I have a waterbox 10 and tunze ato which uses a float valve.
The float is in the pump chamber and reacts to 100ml or less, which is great for stable salinity.
Where is your sensor located?

 

[MaxTremors]

I have two nano tanks (waterbox mini 15 , evo 13.5) Both have open tops and evaporation issues.I have a fz ATO but I'm confused about it's usefulness. In order for the sensor to register that the water level has dropped i'd have to lose enough water to make my salinity rise more than I think is safe. Am I better off just topping off with fresh ro water manually each day or maybe twice a day? I've read that even a slight change in salinity will negatively effect corals and the general health of the tank?

You put the sensor in the return chamber, even if the water goes down a couple inches, that’s only a difference of like 0.0005 or less. On a natural reef, the salinity can vary be as much as a couple ppm (which is like 0.003 or more), equatorial reefs get rain pretty much daily and if they are in-shore they get runoff from the land as well, and during monsoon season it’s even worse. The point is, a slight variation in salinity isn’t a big deal, but an ATO is going to cause less variation than manually topping off unless you’re topping off once every couple hours.

 

[iamahab]

I have a waterbox 10 and tunze ato which uses a float valve.
The float is in the pump chamber and reacts to 100ml or less, which is great for stable salinity.
Where is your sensor located?

I haven't set it up yet. I figured out how to set it up and then realized the water would have to drop about a quarter inch or so before it would trigger the pump. I will try putting it in the pump chamber, hopefully i'll get a better result than I was expecting.