Water Evap

[Frop]

How much water evaporation do you think a 75 gallon (DT + Sump) would burn through? For example gallons/week

 

[GeoffSLC]

My 75 gallon used about a gallon a day. I upgraded to a 125 with a 40 gal sump and it uses about 5 gallons every four days or so. From everyone i've talked to locally, that seems to be right about normal.

 

[Jason mack]

Yes that's about what my 90 g does too

 

[Greybeard]

Depends on many factors. Lighting, heat, humidity, surface agitation...

On my 60g cube, I have to refill my 5g ATO reservoir every 3 days. Under LED's, it was every 5 days. Shows the difference a 250w Halide makes :)

 

[Frop]

Okay I guess I'll need a 5 gallon res. I'm mainly planning what tank size I need next to the sump. Thanks everyone! Well now I'm extremely happy for buying my own RO/DI if it will need that much water. :)

 

[saltyfilmfolks]

I use a 2.5 gal container on my 55 and 30g. Fits better in the stand. A 5g would be awesome.

 

[CarrieB]

I use a 20g tall tank for my 120g. It will last approximately two weeks so handles vacations.

I use a 5g on my Biocube 29 and it lasts forever.:-)

 

[Greybeard]

An RO/DI unit is really an necessary evil if you're going to keep a reef tank. If you live close to a shop that sells RO/DI, and have a small tank, perhaps you could do without, but shops around here charge a buck a gallon or something like that... wouldn't take long to buy an RO/DI unit. I bought AirWaterIce's Dual Home/Reef, and have RO water at the sink for drinking water, and use it to feed the fridge for ice and chilled water. My Eshopps 5g reservoir has a float valve in it, with a ball valve behind that, plumbed to the RO/DI, so when it's empty, I just open a valve and let it fill. Don't really trust float valves, but it gives me some security in case I forget to close the ball valve in time.

Well worth it, IMHO.

 

[Randy Holmes-Farley]

1-3 % daily is typical for most reefs. :)

 

[Frop]

1-3 % daily is typical for most reefs. :)

Interesting. My nano goes through 2 red cups (~ 1/8 gallon) a day. Which is 1% in line with your estimate. My pH is 7.8-7.9 so I heard the higher the more evaporation.

An RO/DI unit is really an necessary evil if you're going to keep a reef tank. If you live close to a shop that sells RO/DI, and have a small tank, perhaps you could do without, but shops around here charge a buck a gallon or something like that... wouldn't take long to buy an RO/DI unit. I bought AirWaterIce's Dual Home/Reef, and have RO water at the sink for drinking water, and use it to feed the fridge for ice and chilled water. My Eshopps 5g reservoir has a float valve in it, with a ball valve behind that, plumbed to the RO/DI, so when it's empty, I just open a valve and let it fill. Don't really trust float valves, but it gives me some security in case I forget to close the ball valve in time.

Well worth it, IMHO.

Ya it cost $9-12 in gas just to get water depending on the car. And usually I'd get 5-15 gallons per run. So this will easily catch up. Not to mention convenience and surety in water quality.

I use a 2.5 gal container on my 55 and 30g. Fits better in the stand. A 5g would be awesome.

I haven't taken any measurement of free space yet. I will before I order anything :) I should have some free space, more so above the sump if I have to make a ledge.

I might try some DIY stuff.

 

[indyjaco]

I'd say 2 gallons every 3 days unless you are using MH.

 

[Randy Holmes-Farley]

Interesting. My nano goes through 2 red cups (~ 1/8 gallon) a day. Which is 1% in line with your estimate. My pH is 7.8-7.9 so I heard the higher the more evaporation..

pH will have no impact on evaporation, if that's what you mean. Salinity does, as does the water temp, the air humidity, the air flow over the water, and the presence of organics on the water surface (e.g., surface scum).

 

[Rick.45cal]

Just don't go overboard, something always to consider with an ATO is the possibility of it breaking... in the on position. Imagine the entire contents of the container dumped into your tank. It happens!

A smaller volume may require more refilling on your part, but it is also less likely to crash/flood your tank if the ATO fails in a spectacular way. Just food for thought! I personally hard plumbed a line from my reservoir to my ATO tank, so I open a valve to manually fill the ATO container. I never have to carry a bucket, it's long enough to last 4-5 days and it's much less likely to cause a disaster if the ATO decides to dump all or some of it's contents in the tank. (I'm sure it still won't be a good experience, but it will limit it's impact.).

 

[Ramturbod]

pH will have no impact on evaporation, if that's what you mean. Salinity does, as does the water temp, the air humidity, the air flow over the water, and the presence of organics on the water surface (e.g., surface scum).

Randy, how does the salinity impact evaporation? I understand the ambient humidity, air flow and temperature as it relates to the temperature of the aquarium water along with the presence of organics not to mention the flow of water at the surface of the tank.

 

[Randy Holmes-Farley]

Randy, how does the salinity impact evaporation? I understand the ambient humidity, air flow and temperature as it relates to the temperature of the aquarium water along with the presence of organics not to mention the flow of water at the surface of the tank.

Water "prefers" to be in salt water than in fresh water. In a sense, it likes to interact with salt ions.

So the air in equilibrium above salt water will be lower in humidity than air in equilibrium above fresh water.

In fact, this is a known way to make humidity standards of less than 100%: put the air above a saturated salt solution. Different salts have different solubilities so they lower the humidity to different extents.

Here are some tables. For example, the relative humidity above saturated lithium chloride in water at 25 deg C is only 11.3% relative humidity. :)

http://www.omega.com/temperature/z/pdf/z103.pdf