Fan position

[Goodair]

Where is the best place to add a fan:
In the canopy with the lights or in the sump, keeping the temperature lower there?

 

[Peace River]

Where is the best place to add a fan:
In the canopy with the lights or in the sump, keeping the temperature lower there?

Interesting question! You didn't mention what type of lights you have and how much ventilation that you have in the canopy or around the sump, but you typically would want to have air flow moving any sources of heat away from the tank before it makes it to the water. If you are running LED lights that put of low or no heat and the heat in your tank is coming from pumps in the water then the answer could be the sump (at that point it depends more on ventilation and how effectively you can move air across the top of the water either in the sump or DT and away from the tank).

 

[bigpaul]

I use T5's and do not have a canopy. I have a box fan that blows across the top of the tank to try and eliminate the heat from the T5's.
I also have a small clip on fan over the sump that comes on if the tank gets above 81.

 

[Goodair]

Sump is pretty hot area, it has perforated board in the back to help breath but the ambient temp is just generally hot in the summer.
Lights are leds but I'm adding single t5 bulb. Figured while the fixture gets installed, I should make room for the fan if it's a better spot to put it the canopy rather than the sump!