Evaporation ????

[duc]

How much seems normal? My house stays in the low 70's, no windows open, no fans blowing, and lighting is minimal at best but I seem to be losing a gallon a day. No leaks (I would have definitely noticed them by now) to speak of, no signs at all of water loss but I topped off my tank on Wed and had to add 3 gallons tonight. Does a gallon a day seem normal?
125 tank
30 sump
Topless
8 36" T-5's
Clif

[::pete::]

I am evaporating 2-3 on some days in a 100.

[MikeDeL]

I lose about half a gallon a day in my 55g.

[duc]

WOW I had no idea it would be that much! My 55 maybe went through 2 gallons a month with lids and this tank didn't seem to loose that much water until I went lidless now it is crazy evap.

[captexas]

Did your 55 have a sump? Lots of surface action on the water like in most sumps can add to the evaporation.

[jlam]

I loose up to 5 gallons a day in the summer when the fans are on pretty crazy evap. on a 100 gallon tank with 35 gallon sump. But I think evap is better than no evap. Gas exchange I think is very important.

Jason

[GaryP]

It all depends on the temp of your tank, how much air movement you are using (fans) and the humidity in your house.

Remember one thing, evaporation is how you control the heat in your tank. You're giving up heat through evaporation. A tank that is covered is not going to evaporate as much, but it will have a tendency to get hotter. It depends on what sort of lights you are using too. MH, of course, will produce more evaporation that PC's. The other down side to a covered tank is that the glass severely reduces the light going to your tank, both through the absorption of the glass and the stuff that build up on it.

[duc]

Did your 55 have a sump? Lots of surface action on the water like in most sumps can add to the evaporation.
No sump on the 55 but my current sump has lids and they are always soaking wet so I can see where it is/trying to evaporate from there. Same with the lids they were always soaking wet (actually dripping) and the build up was a lot to keep clean.

[duc]

I loose up to 5 gallons a day in the summer when the fans are on pretty crazy evap. on a 100 gallon tank with 35 gallon sump. But I think evap is better than no evap. Gas exchange I think is very important.

Jason
Losing 5 gallons a day do you ever have to do water changes? 5 out, 5 in daily seems like your water would be fresh all the time.

[duc]

It all depends on the temp of your tank, how much air movement you are using (fans) and the humidity in your house.

Remember one thing, evaporation is how you control the heat in your tank. You're giving up heat through evaporation. A tank that is covered is not going to evaporate as much, but it will have a tendency to get hotter. It depends on what sort of lights you are using too. MH, of course, will produce more evaporation that PC's. The other down side to a covered tank is that the glass severely reduces the light going to your tank, both through the absorption of the glass and the stuff that build up on it.
Tank stays 78-80 no air movement besides A/C in the house and any/all humidity I have is no because of the tank.
Well I will deal with it now I know it is normal, what happened was I was at work and my wife called saying the tank was real cloudy and making noise. I told her to track down the noise and it was the pump sucking air so I told her to throttle it back and I would deal with it when I got home. Now I am aware I will simply add a gallon each day when I feed.

[StephenA]

Losing 5 gallons a day do you ever have to do water changes? 5 out, 5 in daily seems like your water would be fresh all the time.


Yes! When water evaporates it leaves all of the solids behind in the tank. The only think that leaves the tank is H2O. Salt, CA, Fish Poop, etc. all stay in the tank water. This is why it's so important to keep you water level constant.

My 120 needs about 2 gallons a day. I'd say the MH lighting and sump cause most of the evap to happen. One of the best investments I purchased was an osmolator (http://www.tunze.com/usa/en-gb/dept_304.html). I never come home to a low tank any more.

[Tim Marvin]

Yes you still need to do water exchanges to remove the dissolved solids, and build up of bad stuff.

[Tim Marvin]

Yes you still need to do water exchanges to remove the dissolved solids, and build up of bad stuff.

[GaryP]

Humidity plays a large role in evaporation. I have much less evaporation in the spring/fall when the windows are open because generally the air humidity is higher. When you are running AC or heat, the humidity is generally lower and evaporation increases. I usually have to turn on an extra set of fans when the windows are open to increase evaporation and decrease temp. Evaporation = cooling.

This is exactly why we have central AC here while they can use swamp coolers in lower humidity climates like El Paso. The humidity here is to high for effective evaporative cooling. This is generally not an issue unless you are running MH bulbs.