[jgb23]

ok, I am getting real close to wiring up my whole MH system. I am going to put some fans into the hood. I am running 2 175 MH in a 75 gallon tank. I was thinking 4-3 inch fans (2 in, 2 out). I was thinking of using the Radio Shack fans, but I was wondering how to wire this up. Anybody have a diagram of this or can help me out?

Thanks,

Joe

[charlie]

Why not just wire the fans into individual plugs and throw them on a timer?

[jgb23]

That works, but are there specific fans that can be wired directly to 110? I only saw the PC type fans? Is there another kind at Radio Shack?

[dougc]

Radio Shack has AC (110/120 Volt) fans, but be advised that fans are not all created equal. Many cheaper fans are noisy, which may not be welcome in a living area. DC fans have the advantage that they can be run at variable speeds. The simplest way to do this is using a multi-voltage DC power supply, again something that you can find at Radio Shack. If the fan is rated for 12 volts, run it at 9 and it will be much quieter. Just make sure that the power supply can put the amperage necessary to run the fan.

On my tank, I am using IceCap fans, which are resistant to the corrosive salt air around the tank. They also feature a thermostat that automatically regulates the speed of the fan based on the air temperature. Only on the hottest days can I hear these fans.

The top of my hood is open, so I have a fan blowing IN at each end. Blowing air out of the hood pulls salt-laden air through the fan, most likely shortening it's life.

Both types of fans are easy to connect. There are only two wires. With the AC fans, I don't think it matters which wire is which, since AC fans run in only one direction. When wiring a DC fan, just reverse the wires if the fan runs the wrong way.