Evaporation

I currently have a 90 gal reef set up and evaporate about a gallon a day. My wife and I are thinking of adding another tank or just going to a bigger tank in the 200 gal range and tearing down the 90. We have noticed no ill affects in the house from the evaporation/humidity from the tank we currently have. Is this something I need to be concerned about going to a larger volume of water and having twice the amount of evaporation taking place?

The next tank will primarily be SPS and in my line of reasoning a chiller will be needed. Am I correct in thinking a chiller will slow the evaporation from what I am used to as I currently only use fans located in the canopy for cooling?

 

As water becomes hotter it evaporates faster. So, if you install a chiller and keep the temp exactly where the tank is now then you should have approximately double the evaporation you have now. This assumes that you have the tank in about the same place AND the Surface area of the water in the new tank is about the same as the surface area of the existing tank. As you increase the surface area you increase the evaporation amount. (all other things remaining constant). It is the water temperature at the surface that matters most.

If you cool the tank down a little then you will have less evaporation, again, all other variables remaining equal.

I could probably figure out the evaporation amount mathematically if you gave me the the other variables -but I would rather not. It is easier to just set 'er up and watch it go.

I don't think two gallons a day is a big deal.

 

I would say the biggest would be relative humidity. I'm jealous that you have a 90 and only lose 1 gallon! Up here in the high desert, our 40 looses about 2-3 gallons every day!

 

Going from a fans to a chiller your evaporation will drop although you will have a little more due to larger surface area. Since I added a fan to my seahorse tank I have had to replace 2 gallons a day, prior to the addition I only added a gallon or 2 a week.

In a normal house you should not notice any adverse effects from a 2 gallon a day loss. In fact I have found that in the winter when my humidifier usually runs it runs a little less since I set up my tanks, which is actually a plus as far as I am concerned.

 

How would it be double if the chiller isn't doing anything? Wouldn't the evaporation be the same since the chiller didn't decrease the temperature?

 

Think it depends on a few things. Will the tank be open to the room or will it be a "built in"? Built-in would need to have some way of moving the excess humidity from the enclosed space. It would also depend on how tight your house is. In this day of saving energy by making houses "tighter" we have increased the pollution within the living space. Depending on the moisture barrier you could end up condensing considerable moisture on windows during colder months. Up north this can be a problem. In Atlanta, I'm not too sure what it would take to start getting the condensation. A 220 with probably a considerable sump no doubt would be dumping considerable mositure into the house. If you'll recall when "pogo" built his fishroom he installed an exhaust fan to help with the humidity problem.

 

All things remaining equal - as he doubles his tank size he will double his evaporation. (Approximately)

 

Yes and I have mentioned it to Pogo and will ask again now that the summer is coming to an end which is the time of year I think would give me a problem if any.

I used to live up near you Gary (you know that I think) and having built many houses both in the north and now in the south I can safely say there is no problem building houses too tight down here. lol Just a little different building "standard" where Im at now.

The tank will NOT be built in. Will have a canopy though.

 

in the winter time its better and add moistuer in the summer in Hotlanta I know you have Central A/C or heat pump and that will remove the moisture. Its not a worry ..

 

Im leaning towards this statement. I think what matters here is the type of lighting he has and how long they are on. I also have a 90g and I have to replace about 2-3 gals per week or so. I have no chillers or fans blowing across the waters surface and my temp is always at 77 deg. Luna