Filling her up

TheReefGeek · #1 07-05-2006, 03:20 PM

Yeah probably with my big surface area of water because of my big sump, I don't need the fans for cooling. And yes it is in the basement.

I had a 110 and 50 with no sumps in a second story apartment during the summer and don't remember high evaporation though, but again, no fans across the water at all, my lighting was seperated from the tank so there was little/no heat transfer.

The salinity swings without auto-top off of 10% evaporation per day must be pretty significant?

Johnny Reefer · #2 07-05-2006, 03:27 PM

Quote:

Originally Posted by TheReefGeek

.....The salinity swings without auto-top off of 10% evaporation per day must be pretty significant?

This is what I expected when I first got into Marine aquarium keeping, without an auto top-off, 1 1/2 years ago. But, IME, 10% evaporation caused an increase of only about 0.001 - 0.002 SG.

Cheers

,

TheReefGeek · #3 07-05-2006, 03:29 PM

Thats not too bad at all.

SerLunchbox · #4 07-05-2006, 03:42 PM

I get about a 0.01 - 0.015 swing with SG it seems.

If i can get these lights hung from the ceiling (or raised higher with wood or something) then i THINK i will be ok ... i am thinking maybe another 4" or so.

anyways, i will look into that top off system. Gonna Need something but at least it will be a help!

Johnny Reefer · #5 07-05-2006, 03:47 PM

Quote:

Originally Posted by SerLunchbox

I get about a 0.01 - 0.015 swing with SG it seems. .....

! Are you sure? That's quite a big swing.

Cheers

,

danny zubot · #6 07-05-2006, 06:49 PM

Quote:

2. The fans are the biggest contributor to evap.

How does that work? If the fans are cooling the water then there should be less evaporation, no?

OCDP · #7 07-05-2006, 06:53 PM

I wouldn't even know how to scientifically explain how this works, but I know fans contribute to evap. Even if I turn my bedroom fan on, I get double the evaporation. plus, I've ran fans across my water and I seen horrible evaporation so I had to stop using it.

SerLunchbox · #8 07-05-2006, 07:01 PM

Quote:

Originally Posted by Johnny Reefer

! Are you sure? That's quite a big swing.

Cheers

,

Yeah ... that is generally what i have been reading from the refractometer ... though it doesn't seem right at all.

Given that 5 gallons shouldn't raise the SG that high.

I think i will have to recalibrate it

Midknight · #9 07-05-2006, 07:16 PM

Ok, I think this is how this happens...
Water evaporates cooling the tank, but without air movement the moist air remains above the tank.
Air can hold only so much water so when it becomes saturated evaporation slows down but then the cooling also slows.
With a fan moving the saturated air away it allows for more water to evaporate keeping the tank cooler but also increasing the amount of water that is allowed into the air.
Make sense?

Dan