Apr 06

Cooling Fans for Aquarium Canopy – DIY

The Scenario

I’m sure many people out there have experienced the very same issue I have when they finish making their own Halide Canopy… HEAT! When running my aquarium under 4 compact fluorescents, the water temperature was always between 76-78 F. They fist day I completed the halide canopy¬† the temperature sky rocketed to 83 in under 4 hours!

Although the typical reef temperature in the ocean is around 81 in the summer, the ideal in this hobby is to keep fish stress down. A temperature swing of almost 10 degrees in under 4 hours is not going to cut it.

The Solution

Add ventilation to the canopy using 12V computer fans. and an old DC Adapter almost everyone has lying around.

Parts List:

  1. 1 or 2 12V Computer fans (I chose the Antec 92mm TriCool, very quiet and 3 speeds!)
  2. 1 12V DC Power Adaptor. (Mine is 12V 1A) If you are running multiple fans get one at least 0.5A
  3. Optional: Soldering Iron
  4. Electrical Tape
  5. Wire Strippers or Razor Blade
  6. Wire Cutters or Scissors


Click to Enlarge

Click to Enlarge

1.Cut the end off of the DC Adaptor, peel the wires apart and strip them with the wire strippers or razor blade (be careful not to cut your fingers with the razor blade!).

2. Cut the Molex connector off of the computer fan and strip the wires.

3. Connect each wire separately to the ends of the DC adaptor. (Note: If you are connecting more than one fan, repeat step 2 for each fan and connect each wire directly to each wire on the DC adaptor (Parallel Wiring). This will ensure that each fan will get 12V and will run at the fastest speed.

4. If using a soldering iron, now is the time to solder each of the sides together individually. If you don’t have a soldering iron, use a crimp end or electrical tape.

Click to Enlarge

Click to Enlarge

5. Use electrical tape to make sure all bare wire is covered. Ensure each side is taped individually.

6. Plug the adapter into the wall and watch your fans run!

For best results plug the adapter into the timer for the lights that run the longest. This way when the lights are off, the fans will shut off and reduce excess evaporation in your tank.

The Finished Product

Click To Enlarge

Click To Enlarge

Good luck.

If you have questions, post a comment with your email address and I’ll be happy to answer them!


Skip to comment form

  1. Kelly Brown

    The best information i have found exactly here. Keep going Thank you

  2. Drimo

    Looks great, thank you for the write up and pictures. I am probably going to try this soon myself as I have plenty of PC fans and DC adapters lying around.

  3. 10 gallon aquariums

    Thank for sharing !

  4. Rob

    Is 2 the maximum number of fans that you can hook up before using another power adapter (hope that makes sense?)

  5. Alecia

    Like to talk to you more about wiring. Drop a line when you can.

  6. Joseph

    Depends on the spec of the fan and the power adapter… Most fans will take a decent variation incoming voltage, the more fans you have in series, the less quickly they will spin.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>