License to krill

Tank Evaporation

Hi Guys,

How often are you guys refilling the tank? I have a 65 gallon rimless and I'm probably topping off 5-8 gallons a week. Is this normal?
 

Coral reefer

BOD
Staff member
Hi Guys,

How often are you guys refilling the tank? I have a 65 gallon rimless and I'm probably topping off 5-8 gallons a week. Is this normal?
Yes. Rimless will always have higher evaporation than a tank with lids. Auto top off is a helpfull tool for pretty much any tank IMO.
 

ofzakaria

Supporting Member
Hi Guys,

How often are you guys refilling the tank? I have a 65 gallon rimless and I'm probably topping off 5-8 gallons a week. Is this normal?
As long as your salinity is correct and your ATO is accurate i wouldwoild not care about how much you need to top off. It will depend on your environment.
Am very paranoid of salinity and want to keep it rock solid to control my paramaters. In my 170g main system I go through 25g a week of fresh water with salinity solid around 35ppt -+1.
Important thing is to have a reliable salinity measurment regimen or prob..

Sent from my SM-G960U using Tapatalk
 

The_Lazy_Reefer

BOD
Staff member
I’m at about 9 gallons per week on my 75. When the summer hits and the fans kick on to cool the tank that number goes up quite significantly
 

NelsonCh

Supporting Member
sounds about right. 200 gallon lost 10 gallons every 3 days. temperature kept at 76-78


Sent from my iPhone using Tapatalk
 

sfsuphysics

BOD
Staff member
I lose more in the winter than summer time, mostly because the temperature differential between tank and air tends to allow greater evaporation rates... or at least seems that way. In the summer it never gets "hot" like some people so don't need cooling fans
 

rygh

Webmaster
Staff member
So the physics heavily simplified:
Cold air can hold very little water, so gets very dry in terms of absolute humidity.
As air warms in your house or near tank, the amount it can hold goes way up, so relative humidity drops.
Because of the very low relative humidity, the evaporation rate really increases.
So it evaporates faster in the winter.

Which is doubly bad because at 8,000 BTU/gallon evaporated, really impacts heater electricity use.
 

Flagg37

Supporting Member
Mine was a little over a gallon a day. The footprint was 48”x30” and it was rimless. It’s far drier here in Colorado so I’m curious what my evaporation will be like here. I do have a cover planned for the next build though. I expect that will cut down on the evaporation considerably.
 
Top