How fast does water evaporate?

UkrainianReefJunky · 04-23-2006, 05:04 PM

My tanks been running for only three days and I just noticed a huge amount of bubbles coming out of the return line into the tank!!!! I looked at the sump and it looked like it was running low? No leaks...I don't know what happened? The water level just dropped below the pump intake.

Fly Guy · 04-23-2006, 05:15 PM

Many many variables contribute to how fast the water evaporates. You either need to just get a feel for how fast your does with your set-up and keep it full where it needs to be OR better, set up an auto top off. Type that in the DIY forum for info and youll find its not all that difficult or expensive to set up.

lndlkdreef · 04-23-2006, 07:29 PM

My tank varies in evaporation from day to day. Humidity being the biggest cause. On high humidity days almost no evaporation occurs. On dry days I can lose a gallon or two.

You just gotta learn to stay on top of it and check it every day or two.

Loverotties · 04-23-2006, 07:37 PM

Every tanks diff and the time of yr also.But it also helps for dry heat in the winter!Mine goes something like thisWinter % gallons in two weeks in the summer 5 gallons in 5 days.

Junkzoo · 04-23-2006, 10:24 PM

Yup, you will get a feel to how much you will lose over time,,and like was said it varies a bit with variables like humidity,and outside variables like lighting and water movement and even fans used in canopies , or even blowing across the tank..
My 75 reef tank runs 2-440 w Mh's + pc actinics, in the canopy i have two muffin fans blowing outward, and one inward,,and have a decent amount of water movement at the surface,, i usually end up losing close to three gallons a day, when the lights are on full schedule,,luckily i do not run a sump,so the only thing i have to worry about is the HOB skimmer powerhead getting above the water level, etc.i can tell from the sound of the water from the pumps/powerheads/filter outtake,where my water level is, and if i need to top-off soon, or if it can wait a lil bit,,,,when this tank get upsized to something in the 250g
+ size, I will be having a sump in service, and then i will look into a top -off setup

Twitterbait · 04-23-2006, 10:38 PM

I lose 3 gallons a day. there is some research that shows that evap may have more to do with the actual light hitting the water then the temp and humidity.

VWD · 04-23-2006, 11:22 PM

Every tank and house will vary, It also depends on the time of year for me, I add more sometimes and less other, i have no real answer here, the best thing to do is have an auto top off

Doug1 · 04-24-2006, 01:18 AM

OK you list a 58g tank and 5 gallon sump, in the typical sump setup with overflow and return pump to balance out the display is going to keep the same level as long as the sump holds enough water to keep the cycle going.
As water evaporates the level in the sump will drop, while the level in the display tank stays constant.
Whenb the water level in the sump drops due to evapoaration eventually it will no longer be able to pump a steady stream back into the display, sucking air thru the pump will result in the bubbles going back into the display
With a 5 gallon sump, it wont take long to evaporate enough water to cause this to happen. Your house is heated, the tank is heated and the water turbulence from the display to the sump and added surface area will increase evaporation causing the water level in the sump to drop.
LIght per se, has nothing to do with it directly, evaporation is basically a function of temperature, humidity and air movement. Light can factor in that the more intense the light the more heat thats produced, But as the temp rises, assuming low ambient humidity, the more wate will evaporate. Hot dry weather or indoor heating with low humidity will increase evaporation. Air movement , ie fans will increase evap, causing a reduction in water temp. Thats why fans are used to offset the heat generated by ho output reef lighting.
When water evaporates from your tank its fairly pure water, same process as a still, leaving the salts and stuff behind so adding sufficient amounts of RO/DI water will keep the Salinity and Specific Gravity on an even keel, avoiding swings in salinity that may cause issues with your animal.
Thats why some kind of auto top off device is a good idea, esp if you need to be away for more than a day

Bottom line, the warmer and drier the air in the tanks environment the more its going to evaporate. a hot dry desrt night is going to still evaporate water even if the lights are on

UkrainianReefJunky · 04-24-2006, 07:15 AM

Thanks everyone!! This is why I love you guys. I didn't even know about an auto top off. I'm doing my research and I got a 40 gal tank from my neighbor for free. I'd like to divide it up in 2 sections. One section for RO water w/ No salt (for the top off) and the other section for a refugium. I'll talk more about this in my tank build and post pics as it unfolds.

Thanks again!!!

Cylenchar · 04-24-2006, 02:41 PM

I lose about 2.5 gallon every other day to evaporation in my 55 gallon and 37 refugium.... so roughly ~1.33% of my water a day..... it varies though... if i have the slidding door open, the amount doubles... But, I also live in an arid climate.... even in the winter the air is dry.

Tim224DT · 04-24-2006, 02:47 PM

I have to add about a gallon and half a day to my tank.

Tim

Little Luey · 04-24-2006, 03:09 PM

I add about 5 cups of water on my 20gal a day.

Twitterbait · 04-24-2006, 05:11 PM

Take a look here , this is a discussion about what i was saying earlier with the light hitting the water being a factor in evaporation.

combiemaster · 04-24-2006, 06:30 PM

yeah that was happenig to me too i check my salinity and it was at 1.022 then some water evap and the salinity shot up to 1.025 now i put more water and drew a fill line one the sump now i am measuring how much water i am losing each day so far i lose about half and inch each day dont know how many gallons though.

leveldrummer · 04-24-2006, 08:40 PM

Quote:

Originally Posted by combiemaster

yeah that was happenig to me too i check my salinity and it was at 1.022 then some water evap and the salinity shot up to 1.025 now i put more water and drew a fill line one the sump now i am measuring how much water i am losing each day so far i lose about half and inch each day dont know how many gallons though.

hahaha i thought i was the only one so i didnt mention it. haha, i loose about an inch a day. i have no idea how much that is in gallons or cups or whatever.