Temp. questions... (1 Viewer)

[rxonco]

I've been having a problem with temperature running at about 83 during the day for the last few weeks. I don't have a sump or fuge so I put a clip-on fan to blow across the surface of the tank during the day. This has seemed to do the trick as it's lowered the temp to a daytime of about 80. My question is about the water evaporation. What is the best method of measuring how much top-off water I need to add on a daily basis? Since I don't have any type of automated system, is it going to be a bad thing to only replace this evaporated water once a day?

 

[Guest]

What size tank? Is it a small nano?
Really small nanos with lots of evaporation, should be suffering a heat problem also, but that would raise salinty, but a larger tank, well you don't have to worry about it as much.

Once a day should be fine from what I have heard, just make sure you are using pure water, RO/DI be preferred.

But then this is all just what I have heard.

 

[rxonco]

It's a 72gal tank. I just didn't know whether or not the evaporation lost during the 8 hours that I'm at work would make that much difference in salinity.

 

[imsuperjp]

Just my opinion but a 3 degree difference dont seem like a lot to me.

 

[AggieBrandon]

My frag tank tops out at about 84.4 F during the day and eveyrthing is fine.

Brandon

 

[Guest]

Well how much evaporation was happening before you put on the fan, and the higher temp?

Imsuperjp, taking your quote out of context.
Nope I see no difference if the temp is 104 or 107 while you are running a fever, or that 96.5 for an average human body temp is seen as cold, and 99.5 is running a fever.

But seriously, 83 is not to high, but 85 is, so if he dropped it by 3 degrees by just a fan, then 85 would be 82 instead of 85, and I think that is pertty good thing.

 

[imsuperjp]

I just wanted to add a question onto this. THe top of the tank near the lights seems to be hotter than the bottom. Is that common also ?

 

[Guest]

If the water near the lights is hotter than deeper in the tank you do not have enough circulation.

 

[imsuperjp]

So i need to point some power heads up?

 

[Brad]

I have always pored all my top off water in at one time. Granted I do have a sump. On my 55 I had a 10 gal sump (6 gals of water). I would pour 1 gal of top off water in almost daily. Where the water return plumbing came in to the tank you could see the fresh water "cloud" pumping into the tank. After 10-15 seconds it would be all mixed due to the water circulation. The corals and fish never seemed to mind. The fish would sometimes even swim up to the water return and hang around in the fresh water.

Since you don't have a sump, I would pour the top off water near one of your power heads and just let that mix the water into the main tank. You can pour with a slow but steady stream. Maybe 20 seconds for a gallon of top off?

 

[rxonco]

As far as the amount of topoff...do I just add until I come back to my original Specific Gravity?

 

[rxonco]

That didn't sound too good.

I'm not really noticing very much of a rise in salinity on a daily basis. So does this mean that I'm not really needing much top off?

 

[Guest]

the salt doesn't evaporate, just water, so just add the top off until the water level is back to the level in which you started with.

 

[Guest]

So i need to point some power heads up?

No.
I don't understand why the water at the top of the tank would be warmer unless it is almost stagnant.
Have you ever swam in a lake? In a lake your feet are at a much cooler tempature than you arms because there is no circulation and the sun only heats up the first couple feet of water. At a pool if you dive to the bottom of the deep end there is no difference in tempature because the water is being circulated. The water at the top of your tank and the water in your sump should be exactly the same temp.

 

[imsuperjp]

I dont know either. I have a mag 7 pushing the return pipe so there should be plenty of flow on top