Summertime Evaporation

[Makaiveli]

It's hot so I have a fan on the aquarium, which results in FAST evaporation.

I'm dripping R/O water into the tank to compensate, because when the water evaporates, the salinity goes UP

Any suggestions, considerations, knowledge born from experience?

[Cearbhaill]

Keep that top off going!
Never let it get behind enough to affect your salinity- this is what we mean by stability.

[mogurnda]

Keep doing what you're doing.

How handy are you? You can put together an auto-topoff system using a float valve, or a float switch plus a solenoid valve if you have a little spare time.

Right now I'm just using a solenoid valve on a timer for the 20. For the 90, I am putting a float valve in the sump, hooked to a 16 gallon carboy.