Question on heater placement

[TiGs]

Hello

I have a 75w ebo-jager heater and it is currently completly submerged 5''-6'' below water level and placed horizontal in my tank(10G). Is that ok or should the heater be in vertical postion and be submerged to only where the minimum water level line indicator on the heater? The instruction and doesn't say about placement

 

The reason I ask is because i notice about a 2 degree temp fluctuation less than the set temp(79 degree) of the heater. I've seen it go as low as 77. I was thinking that maybe the lighting is tricking the heater to think it is at the correct temp because of the heaters horizontal placement.

 

thanks

[CRG]

I've read that horizontal placement of heaters is preferred over vertical due to a more efficient distribution of heat throughout the tank, which makes sense. In terms of the discrepancy between your heater and thermometer, I would not worry about it. Perhaps you could purchase another thermometer and take an average if you wanted to be more exact, but this isn't necessary. Ultimately, consistency is what you're after when it comes to temperature, rather than any exact number....within reason, of course;)