Evaporation question

[necrio]

So, my newest tank ( Biocube 29) has been setup for almost two months.

Since day 1, i transferred my stuff from biocube 14 + new sand.

Nothing is suffering, in fact I have never seen such growth and success in any of my tanks as of yet.

I switched from the cheap "Oceanic" SW from the LFS to the slightly better synthetic salt. In addition, I went from a T5HO to a par38 bulb(ebay) and now I am on a Reefbreeder Nano (newest light, came out march) .

Now, my two previous tanks were open top, which accounts for the evap.

However, this cube I have not had to top off ONCE! In fact, in the beginning, the SW was too fresh ( they messed up the mix at the LFS) so It took almost 3 weeks to go from .21 to .25.

How come there is virtually zero evaporation in a tank with a lid?!

 

[Rogger Castells]

the evaporation is going to be similar but de condensation is higher when you have a lid and the vapor returns to the tank in the form of drops, its is similar to the process in a pot of water simmering with a lid on, most of the vapor circulates and condensates back into liquid.

 

[rovster]

Yeah what he said. My bc14 barely evaporated anything. I would top off every few days and barely anything. My 30 gallon goes through about 4 gallons, and my new tank over 10. Before setting up my ato I was dumping a small bucket or two of fresh water in daily!