Heating and what to do's and what to get...

[aaronlp]

Ok over the past few days ive noticed temperature swings in my 75G Display Tank. I have a 30G long sump as well. I run a Bubble Magus NAC6, Mag7 Return, 2x250w metal Hallide with 2x54w-T5s and 1x200w and 1x125w heater in the sump. I do have a fan blowing across the tank when the hallides kick on and it shuts off when they go off. This keeps the temperature over the tank much cooler than what it used to be. I dont know if this is needed but the cellar also have 50-60% humidtity. With the tank being in the cellar it is relativily cooler with room temperature around 68-70 degrees. Now in the summer the temperature isnt much of a deal but this winter has been a pain in the ***. My temperature has been swinging from 76-82 degrees and its causing stress on the tank. im very concerned about the temperature. Now i feel like i have some sim ple solutions that mmay work from askin questions at the lfs.

-Keeping 2 heaters that are 200w instead of a 200 and 125w
-Also ive noticed some techinical problems with the 200w.(It constantly stays on and wont shut off even when you mess with it its like you have to drop the temp all the way down so it shuts off like its a faulty heater or it got dmaged)
-With temperature in the tank rising with the lights bein on then it dropping when the lights go off would having the 2x200w heaters play a different role to help control the tank temp?

Any input would be great i am looking into replacing these heaters with 2x200w heaters to see if there is a difference and setting them to about 77 or 76 degree each.

 

[Jstn]

Get a controller, honestly it's the best way to stabilize temperature

 

[der_wille_zur_macht]

First get your heaters figured out. If one is broken make that your #1 priority.

Next, I'd try to link the swings to their causes. Is there a pattern? Does it hit the low point or high point at the same time each day? What happens at that time each day?

Getting a controller can be a big help but you need to examine the root cause. A controller can only switch things on and off; if you've got some environmental problem or there's equipment causing heating or cooling issues you really need to work that out rather than throwing muscle at it.

 

[aaronlp]

Ive npoticed at night and in the morings its around 75 and when the hallides kick on it goes to about 80 degrees orso and then around 5oclock about an hour or so after the hallides go off the temp start to decline then repeats again

 

[EllieSuz]

If you had a controller you could run the fan(s) when temperatures rise above a certain point. Running the fan(s) concurrent and continual with the halides may be causing the fluctuation. The temperatures in my tank do not fluctuate more than 1/10th of a degree in the winter (79.5) and no more than one degree (80.5)in the summer.

 

[der_wille_zur_macht]

What are your heaters set at? Do you know that they're turning on and off at your target temperature?

If they are, it sounds like you either need more heater wattage at night (if you're targeting 80) or more cooling during the day (if you're targeting 75) or some blend of the two if you want a temperature somewhere in the middle of that range.

 

[aaronlp]

77 and 80

 

[Eastamherstbias]

Get a controller. I have a apex and an apex jr. Both work well, no complaints.

 

[der_wille_zur_macht]

For temperature I really like the idea of using a dedicated, industrial controller (i.e. a Ranco) as opposed to a reef hobby controller, but that's more or less personal preference.

Like I said above though, I really don't think a controller is THE default answer here, since all it can do is turn stuff on and off. If the heaters aren't powerful enough or the fan can't cool the tank enough there's still going to be an issue. IMHO controllers for heating/cooling are really best used as failsafes (i.e. if the heater's own thermostat sticks on) vs. to actually solve heating/cooling issues.

 

[Eastamherstbias]

I have a 400w heater attached to my apex for the basement sump. At most I have a .4 of a degree variation.

 

[aaronlp]

Just put 2 new 250w heater in the sump calibrated them and will psot laster tonight to see where im at

 

[der_wille_zur_macht]

I have a 400w heater attached to my apex for the basement sump. At most I have a .4 of a degree variation.

Yeah, and that's because your heater is powerful enough to keep the temp from dropping too much. In Aaron's case his heaters (probably) aren't powerful enough, so adding a controller won't be a surefire way to solve the problem. A good quality aquarium heater's internal thermostat can maintain a .4F tolerance without ANY external controller, as long as it's powerful enough for the system it's running in.

My issue with reef controllers being used for temperature control is not accuracy or low hysteresis, but independence from other functions and how that can impact long term reliability.

 

[Eastamherstbias]

Correct, but in case of an issue, it will play a sound and send an email. Which tends to be helpful when all hell breaks out.

 

[Jstn]

Yeah, and that's because your heater is powerful enough to keep the temp from dropping too much. In Aaron's case his heaters (probably) aren't powerful enough, so adding a controller won't be a surefire way to solve the problem. A good quality aquarium heater's internal thermostat can maintain a .4F tolerance without ANY external controller, as long as it's powerful enough for the system it's running in.

My issue with reef controllers being used for temperature control is not accuracy or low hysteresis, but independence from other functions and how that can impact long term reliability.

I get that, but the problem I had with my heaters is they would fluctuate day to day based on ambient temperatures. I found this to be the best solution for me, but if your heater is crappy yeah, i could see that being a problem.

 

[Eastamherstbias]

I know it is not the most economical way but it is the reason I have an apex jr running the temp in the main tank and the main apex running the temp in the basement sump. In case something go awry with the other temp sensor.

 

[Cptn Spaulding]

I suppose another question is what brand are these heaters? Aqueon? Marineland? Jager? IME the caliber of heater should to be thrown into the mix, because some are more efficient than others.