Ink Bird Controller and Eheim Heaters: Issues

[Chu'Wuti]

Hi, All, I need to pick your collective brains.

We have two Eheim heaters in a 75-gallon tank, one at each end. We have an Ink Bird Controller running them.

I will confess that reading the Ink Bird instructions really means nothing to me. I have no idea what the actual settings should be. My husband--who is a physicist accustomed to working with gadgets like the Ink Birds, tried to calibrate the Ink Bird (set the zero point) with ice water, but he was not successful. The Ink Bird is showing that the power is on to at least one of the heaters; apparently it's trying to bring the heat up?

Currently, the heaters are set to 81 degrees Fahrenheit. The Ink Bird shows one at 82.8 and the other at 83.0 degrees F. A glass thermometer in the tank shows 82. He and I are concerned that the Ink Bird is not functioning as we need it to function. We're not sure what the REAL temperature is. Can anyone offer a clear explanation of how to ensure that the Ink Bird is properly calibrated and how to set each control element (heating and "refrigeration") so the water stays at 81 degrees (80-82 range acceptable)?

 

[seangee]

If you have 2 heaters plugged into a unit designed for heating and cooling it will heat forever. The idea is that the heating circuit comes on when the tank is too cool, and the cooling circuit comes on if it is too warm, both controlled from the same sensor. my inkbirds were all pretty accurate out of the box. I just checked the displayed temperature against a thermometer I knew to be accurate. There is the abilty to calibrate mine, but its in degrees + or - so no need to use ice water.

All of my controllers are the dual heating type as I don't have any aquarium chillers - and being in the uk usually don't need one. But in your case the heater(s) should only be connected to the heating circuit.

 

[Chu'Wuti]

I started reading your reply to my husband, and he immediately said, "I don't have any heaters plugged into the cooling circuit. I used a dual plug and plugged both of them into the heating circuit. I set a temperature on the cooling circuit just so that an alarm will go off if the temperature drops too low during a power outage."

So I erred in my OP, and I'm still stuck with what's going on . . .

Oh, also--when I ordered the InkBird, I didn't see any option for one that's a dual heating type.

Frustration!

 

[seangee]

Ok I think I understand.

The thermostats on aquarium heaters are not very accurate. They are reasonably accurate but I would not worry about a couple of degrees. Don't forget there are also temperature differences within the tank.
This is what I would do

1. Set each heater to turn off at 83. This is independent of the Inkbird, they should do that if plugged directly into a power socket. That way if the inkbird fails to turn off (or the probe fails) the heaters will shut down before the tank gets too hot. If the Inkbird works correctly it will shut the heaters down just before they reach this temp..
2. Set the Inkbird to turn off at 82 - This is the target temperatute (t on mine) - when it gets to 82 the inkbird will shut off power to the heaters. The Inkbird protects against the thermostat failing in one or both heaters.
3. Set the Inkbird to come back on at 80. When the temp hits 82 the heaters shut down and won't come back on until the temp drops to 80. On mine this setting is d=2, where d means difference.

I don't know about the cooling circuit or alarm because mine does not have these. The above describes how I have set mine although my range is 23-25 because I don't understand farenheit