tank heat loss at night

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Sahabo

Aquarium Advice FINatic
Joined
Mar 22, 2008
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Location
Portland, Maine
Advice for a newbie!

I have a 5.5 gallon, filtered, heated glass tank with a hood. I keep the temp at about 80 degrees for my betta. The problem is that we turn our heat down at night to about 62. Now, I thought that the hood and the heater would keep the temperature steady. But every morning I wake up and the tank thermometer says that the temp is down about 2-4 degrees. Is the tank losing heat through the glass or the small cutouts on the back of the hood? Is there some kind of insulation I can put on the outside of the tank to keep the temp stable? I have also thought about getting some adhesive background for the outside of the tank...would that help insulate the tank? Also thought about styrofoam or that reflectix stuff.

Looking forward to hearing what has worked for you! :n00b:
 
Is the light on during the day? The heater should keep the temp steady. I would bet the lights are warming it during the day.
 
I keep my house temp at a steady 76 degrees constant helps for my betta tank that doesn't have a heater. Plus my wife likes to Roast since she was raised in California. I usually have to go outside if I want to cool off, Much easier than fighting with the wife.

The heater for your 5.5 gallon should keep the tank warm no matter what unless its set wrong or defective. What kind of heater is it?
 
My heater is a Visi-therm stealth 25 watt. I have the hood light on during the day and off at night, about 12 hours on, 12 hours off. Any we have to turn the heat down at night to save money and to keep my husband sane and able to sleep :)

Maybe the heater isn't working well? It's only a week old. I have a cheapo liquid crystal thermometer on the outside of the tank, and it usually says that the temp is about 2 degrees lower than what I set on the heater.
 
Any we have to turn the heat down at night to save money and to keep my husband sane and able to sleep :)
liquid crystal thermometer on the outside of the tank.

I wish my wife was so nice LOL
I would suggest buying a floating glass thermomoter they are much more accurate I have a stick on as well that reads 78 when my floating glass thermomoter reads about 81 The Visi-Therm heaters have a really good reputation for quality so I would try a new thermomoter first.
 
Try not turning the light on for a day and see if the temp holds steady. If it does then just up the heater a bit and all should be well.
 
The temp settings on the heaters are guesstimates only. They get you in the ballpark, but you may need to adjust up or down as necessary.
 
hmmm. well, I will definitely pick up a floating thermometer to see if that helps get a more accurate reading. I'll also try keeping the light off to see if the temp stays stable.

Regular routine:
I set the heater for 80. Turn the hood light on at about 8am. When I get home at 5:30, the liquid crystal therm reads 78. Before bed, I turn the hood light off, we turn the house temp down to 62. When I get up, the therm reads about 76. We turn the houst temp up to 70, I turn the hood light back on, and by the time I get home again at 5:30, the water temp is back up to 78. It hasn't reached 80 yet.

Even if I adjust the heater a bit so gets to 80 during the day, I'm still concerned that it's going to drop at night when we turn the house temp down. Do I have to turn the tank heater up every night to compensate? A lot of people say that glass tanks don't hold heat well and that's why I was considering insulation. But it's such a small tank, I think it should hold its heat!
 
Actually small tanks loose heat faster. Higher aquarium surface volume to total water volume ratio. Makes it easier for the heat to escape quickly.
 
It might be that your heater is kicking off at 76 degrees. Maybe if you set it a little higher, it might stay at 78 over night. The setting on my heater is more than the actual temperature of the tank.
 
Do you have the heater turned all the way up at night and it still drops?

Lets start with the fact that the heaters are rated for the tanks at an ambient room temperature of about 70 degrees. at those ratings most of them are able to raise the temp up about 15 degrees above room temp. if your heat is set down to 62 at night then you might not be able to get the tank up to 80 degrees at night. the light will add some heat to the tank but more than likely the room temp during the day brings the starting temp up so that the heater can bring up the temp the rest of the way.
I keep my house down to 60 to save on heating oil and i need to put 625 watts turned all the way up in my 40 gallon to keep the temp up at 86 degrees (treating for ich) but i use 400 watts regularly during the cold months instead of the 200 watts that says would be for a 40 gallon. during the summer i'll be able to cut back to the 200 watts since the house will be a lot warmer.
you could try covering the tank with one of those styrofoam coolers/warmers at night to keep the temp stable.
 
Well I keep the tank heater up at around 82 at night, and in the morning the water is still about 76. Maybe since we turn the house temp down at night, I need to get a 50watt tank heater to compensate for the room temp? I'll also look into some styrofoam for insulation.
 
Or you could just set you're aquarium to 76 degrees. That really is plenty warm for a Betta.
 
Fish Eggs is correct - most heaters will bring tank water up approximately 9-10 degrees above an ambient room temperature. If the 25 watt heater is not giving you the results you want, you could get a 50 watt heater for the 5.5 gallon tank. I have a 75 watt heater in one of my 10 gallon tanks (a 50 watt heater is the "standard" wattage for this size tank). I had a 75 watt heater lying around, so instead of buying a new heater, I just used what I had. I have been checking it carefully and it is not overheating the water.

I use a digital kitchen thermometer to measure the water temperature. With any brand of heater, the numbers on the dial may not correspond exactly to the temperature that you get. I think I have my heater dial set to 76 or 77 (hard to tell since each degree is not marked) and it's keeping the tank a very steady 80.2 degrees. I believe 76 degrees is too cool for a betta.
 
Yes I think 76 is too cool for him...at that temp, he loses energy and clamps his fins. I picked up a glass therm today and hopefully I will make sure to get accurate results. I will try insulating and turning up the heater at night. If none of that works to my satisfaction, I'll get a 50 watt heater. I am really appreciating all the helpful advice. This forum rocks!
 
I recently moved my betta from a 5.5 gallon to a 10 gallon tank. I put the 5 gallon in the basement when it was empty, along with the equipment I was no longer using (but not the filter!) Today it was very warm so I took the tank outside and rinsed it out with the hose. I noticed that the heater I had in there was a 50 watt Visitherm Stealth. (I wondered where it went!) Anyway :) the point is I have used a 50 watt heater in a 5.5 gallon tank, and it worked out fine and didn't overheat the water. When I set up the new tanks, I measured the temperature every day at feeding time when the lid was open, and adjusted as necessary.
 
FijiWigi, you were so right about the floating therm! When my stick-on says 78, the glass floating says 81, which is almost exactly what I have the tank heater set to...sheesh. well, it will be interesting to see what the new therm says in the morning. Didn't get any insulation yet so I'll just use a towel over the top tonight to see if it helps.
 
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So last night I turned the tank heater up to 84 and covered the top with a towel. What do you know...this morning when I woke up, the water was a steady 80 degrees :D. Turned the house temp up, turned the tank heater back to 82, voila! This might be my solution, at least for now. I might get a 50watt in the future which might eliminate the need for adjusting, but that will have to wait until I get a job. Thanks to all for you guidance and responsiveness!
 
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