Temperature rising with heater turned off ... any ideas?

[olliesshop]

Well ... I think I've got it figured out, at least enough so the temperature dropped to 78 degrees (I didn't want it to go any lower).

It looks like the primary culprit was the hot air vent.  It was blowing directly on the Canister filter from less than 6" away.  Also the vent was blowing directly at the bottom of the tank, since the vanes were pointing upward.  So I moved the filter about 3 feet away from the vent and also directed the vent downward toward the floor.

The secondary culprit was the heater.  I have to unplug it or set it to off to lower the temperature.  Even the slightest adjustment upward will make it too hot.  So right now I'm testing how much of a "micro-adjustment" I need to make.  It's probably going to 1-3% turn of the knob on the top of the heater.

Other factors include;
• The lights, which are on 13 hours a day for my plants
• The top is very well sealed to keep the Cyps from jumping out, which does a really good job of keeping the warmth in.  I know this, because when I resealed the tank last month, I had the lid off and it was difficult to get the temperature high enough.

It appears this will be an ongoing project ... I'm going to try to stabilize the temperature to 79 degrees.

Thanks again for all the help 

[cranialdisturbance]

If you are having that much trouble with your heater I would consider getting another one if you can't get it sorted out pretty quick.

[four_by_ken]

If you are having that much trouble with your heater I would consider getting another one if you can't get it sorted out pretty quick.

Same think I was going to say.  Get rid of it ASAP.  Take it from someone that has had a lot of heater troubles.

[olliesshop]

Good idea on the heater. 

I've already switched it with another one I had and they both seemed to have the same problem.

Both of the heaters are Aqueon Submersible Heaters.  Is that a good brand?  What brand/model would you recommend for my 125g tank?

Thanks again for the help!

[mibwb]

nn

[Regalblue]

Go with two 150w Jager

[cranialdisturbance]

I second Blair's advice. I use Eheim Jagers in all my tanks. I've only had problems with a couple used ones that I bought, and they were older models. Heaters are the notorious weak link in the aquarium chain. There is no completely bulletproof heater. Eventually, given enough time they will either stop working or go into 3 mile island mode.

[olliesshop]

Cool!  Thanks for advice.  Time to go searching.  It looks like Jager's are the way to go.

[olliesshop]

FYI, I've given the new Jager heaters some testing time and wanted to let you know they're excellent, so thanks for the recommendation.

The temperature setting is very precise, by turning the dial by a click or two.  The only problem I had, which isn't a big deal, is temperature number on the dial does not match the temperature at all, even with the calibration maxed out.

 

[Mastiffman]

Definitely seems like a few factors that played into the high heat. I would guess that the 4 39watt bulbs on for 13hrs over a tightly sealed top would be the main factor myself. But then the vents may help as well.

 Glad its all figured out.

 I like the Marineland accutherm heaters. Only thing about them is that you can get bad batches of heaters with bad thermal resistors that burn out quick. They are located at the bottom of the heaters heating element and can be easily removed and jumped with solid wire and crimped.

 I've heard of heaters sticking in the on position before. This can be alleviated by pulling the heater apart once a year and quickly sanding and then polishing the contacts on the thermal arm and circuit connector and reassembling with a smidge of silicone to make the glass and unit water tight again. Works like a Charm. Definitely worth the 20-30 minute task of maintaining the contacts.

 

[olliesshop]

I agree, I think the lights played a role in the high heat, especially with the tight lid holding the heat in. 

It's so nice now to be able to set the heater dial, one click at a time, and have it precisely raise or lower the temperature.  It seems like it's about 0.5 degrees per click.

Thanks 

[four_by_ken]

FYI, I've given the new Jager heaters some testing time and wanted to let you know they're excellent, so thanks for the recommendation.

The temperature setting is very precise, by turning the dial by a click or two.  The only problem I had, which isn't a big deal, is temperature number on the dial does not match the temperature at all, even with the calibration maxed out.

 

I dont even pay attention to the dial setting temperature on the heater itself.  I just put the heater in the water, which is up to temp alredy, and then slowly turn the heater up until it turns on, then back it off a hair.

[olliesshop]

Agreed, that's how I started when I added the heaters.  But now that I have it dialed in I can adjust the temp 1 click at at time reliably.  With regard to the dial setting, it's way off (about 5 degrees too low, even with the calibration dial maxed out), so I have to ignore the reading on the dial too.

Now I'm patiently waiting for my Cyprichromis Coloratus to spawn ... The male has 3 females he's been courting for a while, but nothing yet.

Thanks.