99.99% of the time true. Unless the tank is too cold. Then, you'd want to slow evaporation. Not a problem now in the summer, but anytime you have a heater running, slowing down evaporation will insulate heat.
People dont often consider the IMMENSE amount of energy that is consumed in evaporation. In our aquariums, that translates to heat loss. Evaporation isnt just a nuisance, its necessary.
If you use glass tops and a big chiller, you'll eliminate a lot of the evaporation, but you'll be using a lot more energy to get the heat out, and you need a place to dump the hot air.
grouper therapy;536153 wrote: Never mind I figured it out .you were referring to excessive loss of water in a time period as it may be a leak etc. instead of evaporation,