Strange heater issue.

Hi guy's, my names John and I've just joined this forum after starting to set up my first marine tank 2 weeks ago. I'm having problems with a drop in water temperature at night and some curious test results that maybe some of you have come across before? I have cleaned the filters to ensure that the intended amount of water flow is passing the heater.

My tank is a Juwel Rio 180 litre which includes an internal filter with an integrated 200 watt heater that I have set at 27 degrees Celsius.
During the day the tank will reach 27 degrees but at night drops to between 24 and 25 degrees. I assumed that the heater was struggling to maintain the tank temp once the T5 lights had turned off and the room temperature dropped, but i was wrong.
As the heater is enclosed I can't see when the heater is activated so I plugged it in using an energy monitor which displays when the device is active and measures total energy used. When I installed this monitor the heater was coming on and off on the thermostat and staying at around 26.5 degrees tank temp. However once the aquarium lights went off I have proof that the heater did not operate again all night and this morning my tank was at just below 25 degrees. I need to test this further by turning the lights on in the morning and seeing if the heater kicks in but this morning I had to leave to work. If past measurements are anything to go by the water will be back around 26.5 degrees when I get home.

My questions are: Has there ever been a history of a heater being effected by weather the lights are on or off before? (my lights are plugged into a different wall socket before anyone suggest i'm loosing the supply feed when the lights are off.)

And secondly, if the thermostat on my 200 watt Juwel heater is set at 27 degrees, what is the general acceptable temperature difference between the thermostat being on and being off?

Many thanks for reading and sorry for the UK capacity and temp' units

John.

 

Hi John, welcome to 3reef.

I do not the specifics on your heater type/system. When it comes to heaters though a generalization can be made, if you have any doubts as to the integrity or accuracy of a heater always invest in another heater, preferably a better brand.

Heater malfunctions can be extremely costly and a huge disappointment when livestock is loss.

After googling tank type it looks like a very nice system, but I would either replace the heater now or watch it very closely. The only relationship between how a heater functions and the lighting is going to be that the heater does not come on as frequently once the tank warms up from the heat of the T5.

 

+1 Also be sure your heater is large enough for your system. If you are looking for a good brand of heater try Eheim Jager.They should be readily available to you and are quite reliable.Good luck!8)

 

Welcom John,

Sometimes more than one outlet is controlled by a light swtich. Are you positive the outlet you have the heater plugged into is not a switched outlet?

 

Grawyl, I was going to ask the same thing. Is it possible the heater is on a switched outlet that you keep on during the day but turn off at night?

 

Ever see the commercial where the guy is standing in his garage flipping a switch up and down and asks his wife "i always wondered what this switch does??...", while at the same time his neighbor (older woman) is backing her car out of the garage and garage door is going back and forth as the guy is moving the switch... Very funny ad.

 

I've never had a heater change temps in the tank based on whether the lights are on or off.......