Let's Help Newbies & OGs

[urbanknight]

How much water does your tank evaporate on a daily basis? There are several factors effecting evaporation. However, if you will kindly answer this question and provide your tank size, it will give others a ball park idea of what to expect from their own tanks. Bear in mind things like season, circulation and volume will effect the outcome. However, here is a generalized statement that holds true. A 40 gallon tank will evaporate about 1/2 gallon of water per day. Give or take. Remember that the evaporation is fresh water only. The salt stays in your tank. You must top off with fresh RO/DI water. I know this is basic information but someone who is just starting needs it. Please follow this thread by posting information about your system as I have below. Feel free to add information in reference to evaporation that others may find useful.

My system is 140 gallons. Evaporation rate is from 1.5 - 2 gallons per day. I use a Tunze 3155 ATO.

 

[bg2311]

200 total gallon system volume between display and frag tank, ~ 2 gallons per day at the moment in the summer with the rolling AC running during the day in the same room and the ceiling fans on in both rooms. Neptune ATK. Tank temp is 78-78.5F. No active cooling (no chiller/no fans on the tank).

 

[qasimja]

170G total volume about 1 gallon a day

 

[biswas121]

130 gallon system.. 10 gallons in last 3 months..


Sent from my iPhone using Tapatalk

 

[ptreef]

~750g system. 1HP chiller keeping the system about 80 deg. 20-25g evap per week

 

[Adam]

The biggest factors with the amount of evaporation is the amount of total system surface area, running temp and the amount of flow that actually breaks the surface tension. From there the variances that come into play are the ambient temperature and humidity, which generally vary seasonally. Barring the different possibilities in sump sizes, a 180 and 220 have the same footprint and will evaporate at the same rate. But if the 180 is 2 degrees warmer and has more flow at the surface it will evaporate more over the same 24hrs than the 220 will.

My system is 660 gallons, runs at 77 to 79 degrees with an ambient temp of 68-72 in the winter & 72-78 in the summer. The total surface area is; Display 32sf (4808sq. in), Sump 12.5sf (1800sq. in) & Frag Tank 8sf (1152sq. in). For a total of 52.5sf (7760sq. in).
It will evaporate 27~35 gallons a week. But I haven't seen a winter yet and that number will likely go up from November thru March.

If everyone lists their total surface area we should be able to get a reasonable forumla to get a range of evaporation per square foot. Right now for me its 0.514 to 0.667 gallons per SF.

 

[Reefer-Madness]

My 50g (24”x24”) probably evaporates a little over a half gallon a day. It’s an open top tank and the temp is set to 78 while my apartment usually stays pretty cool at 70 degrees. Some of that is coming out through my skimmer though because I started carbon dosing so the collection cup fills up quicker than it used to.

 

[Frigus Reef]

20 gallon long, I use about a liter of top off per day in the summers and about a liter every two to three days in the winter.

 

[Dmitri]

I’m about to install whole house dehumidifier to replace three small ones that running in the basement. I wonder how it will change my humidity and evaporation rate. Currently my humidity stays between 50-55, I’m hoping it will drop to 45-50.
Dehumidifier is rated to pull out 120 pints of water per 24 hours, that’s about 12 gallons per day.
Currently evaporation is around 10 gallons but maybe with this new equipment it will be higher.
I’m not sure how much surface of water space I have, but I’m running two fans right at the water level of the fish tank. About 1400 gallons of water in the system.
Water temperature 77-78
I use Neptune ATO and to auto refill ro water.

 

[jason7274]

20 gallon long, I use about a liter of top off per day in the summers and about a liter every two to three days in the winter.

Building a 20G long now. Good info!

 

[wantsummora acropora]

170 gal total volume. tank temp 78.5-79. Neptune ATO. Mine evaporates about 5 gallons every 3 days. ceiling fan very close to the tank and runs on high 24-7. Room temp is set at 73 degrees.