Poll: Daily Evaporation - How Much?

dbl · Dec 12, 2017

It's often asked what is the normal amount of evaporation. I really don't think there is a "normal" because there are many factors that come in to play when discussing evaporation and we all have to deal with it based on our own circumstances.

So the goal here is to get a range from the members on the amount of daily evaporation. Let's look at a percentage instead of an amount.

Randy Holmes-Farley · Dec 12, 2017

In my system, it varied greatly with season. I voted near the higher end of what I usually saw.

Deinonych · Dec 12, 2017

Randy Holmes-Farley said:
In my system, it varied greatly with season. I voted near the higher end of what I usually saw.

Same. My evaporation trends higher in the winter, as the air is drier in my fish room due to my home's heater running more often.

Fumanchu · Dec 12, 2017

Same i have almost double the evaporation in the winter and it also varies with my turnover from my sump

Dsnakes · Dec 12, 2017

Don't judge me

I'm not a mathematician....but how do I calculate this? A 5g bucket of water lasts as top off for roughly 14 days. I have a 20g tank if that matters.
5g / 14 days = xx%?

SashimiTurtle · Dec 12, 2017

Very humid summers in SC, moderatly humid winters. That said I have central HVAC with gas heat and I keep the house at 70°F year round. That is as long as the A.C. can keep up in the middle of the summer, sometimes the temp creeps up to 74 with the unit never cutting off. My house is much drier in the winter due to the gas heat. I think this causes my evaporation to be a bit higher in the winter.

All that being said, I haven't actually measured my evaporation. When ever my ATO reservoir is low I add a little bit to it. I don't store a bunch of RODI so I may have a gallon or at most four on hand at the time. My reservoir is a biotech jug that is labeled as five gallons, but will hold about six all the way full.

dbl · Dec 12, 2017

Dsnakes said:
Don't judge me I'm not a mathematician....but how do I calculate this? A 5g bucket of water lasts as top off for roughly 14 days. I have a 20g tank if that matters.
5g / 14 days = xx%?

Your 5g bucket lasts 14 days, so that's 5/14=.357 gallons per day. .357/20 would be 1.8% +/- per day.

Dsnakes · Dec 12, 2017

dbl said:
Your 5g bucket lasts 14 days, so that's 5/14=.357 gallons per day. .357/20 would be 1.8% +/- per day.

Thanks! I couldn't think how the tank size was equated in. Would you believe I am a math teacher?
....me either, good thing I'm not!
I placed my vote!

brandon429 · Dec 12, 2017

im not good at math either, thankfully theres a non math way to reef

do respect the maths tho, the way a chemical trick always occurs somewhere in the link that changes outcomes, seems never ending. those who can memorize the chains effectively Ive always respected.

Voted for least evap, a reefbowl's #1 first obvious physical attribute is that its evaporation restricted, doesn't use auto topoffs. It uses weekly manual topoff of about one or two ounces. a one gallon reef will beat the inherent salinity stability of any reef on the web, its not like we get the good fish to keep might as well play up what a vase does best.

system volume has literally nothing to do with salinity stability

Crabs McJones · Dec 12, 2017

Right now with it being winter and the heat being on, i'm going through 5 gallons every 4 to 5 days.

saltyhog · Dec 12, 2017

As noted above it varies greatly from season to season and your climate. Where I live the winter humidity tends to be very low and the heating methods used tend to lower it even more. In the winter I may see evaporation as high as 2% (a little over 3 gallons in a 160 gallon system). During the summer our humidity is very high and my evaporation falls to almost half that.

I have a 16 gallon ATO reservoir. I have to refill it every 5-6 days in the winter and every 10-12 days during the summer.

Shigshwa · Dec 12, 2017

In the winter, I've noticed as much as 2.5 percent of my 40B per day. I think the larger surface area per gallon of water drives the evap higher, paired with lower winter humidity.

money88 · Dec 12, 2017

I am at close to 5 gallons every 3-4 days in my 40B with 20L sump

smiley28 · Dec 12, 2017

I had to amend my original vote cause I didn’t read the OP so yeah.. I don’t know what I was thinking haha. I think somewhere around 1% daily is what I top off but originally I was thinking weekly to 10 days and was like man no one voted 3%+???? What is wrong with my tank?!? But never mind

Also is that a lot for a 10g? I do have pretty high return flow probably 20x turnover.
Oh and I’ve been running one of the SantaMonica nano ats systems which causes a decent amount of salt spray/creep from what I can see.