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evaporation rate

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Hey all

I was wondering if there's a way to calculate the rate of evaporation from a tank. I ask because I'm currently losing approximately 3 gallons of water a day from my 180 gallon system. This seems like an inordinately high rate of evaporation.

Also, I'm calculating this by measuring the water level in my sump.

Thanks all!


Mike
 
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Sounds like a reasonable amount to me. I add between 80 and 96 ounces a day with my 50 ga and my flow and lighting are on the low side.
 
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I agree. Doesn't sound unreasonable. In you 100gal I loose about 1-1.5gal of water a day.
 
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Thanks patchin. Gotta get my topoff water running again.
 
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With my 75G and 55G sumpu fuge I lose about 10g a week right now. I'm looking forward to getting my ATO installed next week. Should help a lot in keeping my levels more consistent.
 
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That's probably not too high. For my 20g (and now with a 10g frag tank) I lose about 0.5 every day.
 
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Aye, I just realized it's having a pretty significant impact on my salinity levels as well. I had no idea I'd have to top off this much water per day. Chalk another one up the "lesson learned" column.
 
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The mathematical equation to describe the evaporation rate of a turbulent aquarium surface in a dynamic environment is well beyond what anyone here wants to tackle :P That said, 3g might be normal. It depends on surface turbulence, air exchange, tank and room temp. In the summer, my 40g tank evaps about 1g/day and it is in a room that stays below 80deg
 
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[quote author=Gomer link=topic=5668.msg71060#msg71060 date=1229924697]
The mathematical equation to describe the evaporation rate of a turbulent aquarium surface in a dynamic environment is well beyond what anyone here wants to tackle :P That said, 3g might be normal. It depends on surface turbulence, air exchange, tank and room temp. In the summer, my 40g tank evaps about 1g/day and it is in a room that stays below 80deg
[/quote]

Nerd, lol.

I evaporate about 2-3 gallons a day in my system. ~250 gallons total volume. ATO is key when you are evaporating that much.
 
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ahhhh that is where my problem is. I wondered been trying to bring my Salinity down slowly and even with 3 gallons a day been only slightly going down. Happy to say im at 1.027 thinking i might try 4 gallons till my tank gets to 1.025. Good thread.
 
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[quote author=Gomer link=topic=5668.msg71060#msg71060 date=1229924697]
The mathematical equation to describe the evaporation rate of a turbulent aquarium surface in a dynamic environment is well beyond what anyone here wants to tackle :P That said, 3g might be normal. It depends on surface turbulence, air exchange, tank and room temp. In the summer, my 40g tank evaps about 1g/day and it is in a room that stays below 80deg
[/quote]

Haha, thanks Tony.

I guess ATO may be the way to go. I honestly had no desire to set up an ATO system, but now it looks like I may very well have to. I can keep lugging 3-4 gallons of RO from the garage to the family room every day, my wife would notice the water trail soon enough :P.
 
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I ran without an ATO for years on a FW tank and a year on salt. Once I got one running, I kicked my self over and over for not getting one sooner.
 
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[quote author=Gomer link=topic=5668.msg71066#msg71066 date=1229926758]
I ran without an ATO for years on a FW tank and a year on salt. Once I got one running, I kicked my self over and over for not getting one sooner.
[/quote]
+1!!!!
I probably lose 2-3 gal day on a 200 gal system. But who keeps track, once you set up a ATO and in my case an automatic RO/ DI system using garden timer, it's one of the nagging chores eliminated. ;D
 
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My tanks the same, close to a gallon per day for a 70 gallon system. When I run my fan, It hits a gallon if not more. Just got an ATO and I love it!!!
 
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How much does an ATO cost? My monthly "pets" budget is tight.
 
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http://autotopoff.com/
I got their double switch.
I use an aqualifter on a 5g jug of kalkwasser.
The AL is cheap, but it has very little power (which is sorta good!). It won't pump much much beyond 2ft vertical difference between the output and the reseviour water level. If you are pumping into a sump, it shouldn't be an issue though.
 
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I have been using JBJ auto top off for about 10months now and have been happy with this setup as well. It runs around $100 but you still need a small powerhead to drop in your top off bucket. It also has two switches.
 
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Another vote for the JBJ. I ran without a auto top off for the longest time and once I installed one, it made a world of difference.

[quote author=alve link=topic=5668.msg71087#msg71087 date=1229963005]
I have been using JBJ auto top off for about 10months now and have been happy with this setup as well. It runs around $100 but you still need a small powerhead to drop in your top off bucket. It also has two switches.
[/quote]

I have about a 180g display + approx. 35g for sump (total volume of approx. 215g and lose about 2-3 gallons a day. Not running any halides just 10x54w T5s. For my old 75g display I ran the aqualifter as my top off pump and it was decent, not the best. I lost about 1.5 gallons a day on that.
 
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I just ditched my peristaltic pumps (which I was using for two part). They're too noisy and I've had it.

I'm going back to the cheapo aqualifters for two part and a float valve for top off.
 
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