Heater Temperature

[Barbie Bubbles]

I have 2 new (2mth) Jaguer heaters in my 120 gal. tank. One on each end. They were working perfectly well and kept a steady 78 degree temp. and were going off an on alternately. Last week I hooked up a second canister filter (to seed it to start a second tank) and within 2 days the temp. shot up to 81??? I did not adjust the heaters nor move them and the intake and water return spouts are not near the heaters. I've been turning the heaters down each day by a degree and now have them set at 74 and the temp. did not drop. First question...did the second filter raise the temp? and why can't I lower the temp? P.S. one heater is on a lot and the the other is not going on at all?

 

[bare bottom]

i know your seeding but have you tried turning off the second filter and seeing if the temp drops?

maybe it caused a dead spot around one of the heaters so theres no water flow around it?

could try making sure both heaters have sufficient flow around them with both filters on.

hopefully someone smarter than me will have an answer too.

 

[blue acara]

Heaters, even of the same make and model set to the same temperature will sometimes heat water to different temps. imo the thermostats are wrong.

for example i set my heater to 23 c and it gives me 25 c.

 

[CdoGG]

I am having a similar problem. I have one 400watt heater in the middle of my 90 gal tank and I have to keep it to the lowest setting of 72F and I still have temps between 80-83.

None of the water flow is pointing at it, I am going to try moving my heater in front of the output of one of my filter and see what happens.

I think I might have the "dead spot" issue.

I have bought 3 heaters because of this, I think I have put them all in the same location (middle) too....

 

[Barbie Bubbles]

I don't want to turn off either filter because I don't want to lose the bacteria. I know the temp. increase has to do with some type of change with the water flow because it definately rose a day after I added the second filter. Now one on the right is on most of the time and i set it down to 74 and the one on the left is set on 81 and it's not going on at all. Has to be the way the filters are sucking up the water and pushing it around. Tomorrow I'm going to move the heaters around and see what happens. P.S. the main reason I put one on each end is because my tank is very long 5' and It prevents cold spots. And before I screwed the temp. up by adding this second filter they worked so great for a whole year they were accurate byas close as one degree to the setting I chose. They must be really sensitive as to where they are placed such as the middle, sides or near any filters.

 

[blue acara]

You talking about dead spots. eg the water around the heater isnt moving, therefore the water around the heater is hotter so it shoudd turn off quicker- but it doesnt. Mabie its because you have added the second filter and removed the dead spot that the heates is always on?

Mabie it is just the water flow- just seems like the statement above sounds logical.

Ive got two identical heaters that have to be set at different temps to produce the same temp in the same tank.