Float switch wiring question.

[CodeToad]

I plan on setting up an auto top off system using a float switch but I have a few questions. I want to use an air pump setup, the image attached shows how I plan on wiring it. Here is my problem. I want to be safe and not start any fires, so I was going to get a DC or AC adapter and step down the power to about 25 Watts, but the pump I have says on the back 115V 60Hz and 3Watts. I'm not sure if using an adapter will even work?

I am wondering if it is safe using a float switch from www.floatswitches.net which states:

Maximum Switching Rate 20W Maximum Switching Voltage 200V Maximum Switching Current 0.6A Contact Withstand Voltage (DC) 250V Contact Resistance 0.3W max Temperature Range 122-F

Should I use this with out any adapter or is it better/safer to do what I described in my drawing but with an AC adapter. Basically I have gotten myself confused, so any help would be greatly appreciated. I appoligize if this is a stupid question, but I'm slow when it comes to electronics.

[H20ENG]

You are on the right track, only putting low power through the float. Now you need a low voltage relay to hook your 120v air pump to.

[texasreefer]

If you follow the attached thread there is a diagram on how to wire up a float switch using a relay. I'm in Saudi right now teaching instrumentation and I'm trying to teach them relay logic right now. The advantage of using a relay is you can use different voltages and also use the relay contacts to control a device that pulls too much amperage for the switch you are using. Personally I just use a 120VAC relay and a standard pump. If you feel safer you can use a 12/24 VDC relay.
http://archive.reefcentral.com/forums/showthread.php?s=&threadid=195156

[Teo]

here is a simple diagram that may help if you go that route.

I noticed in the link that Texasreefer posted, the post that I maid, I didn't leave a link.... here it is to my top off if interested.

http://archive.reefcentral.com/forums/showthread.php?threadid=126978

good luck

edited... in the dia. that is a 12vdc 400 ohm coil w/ 120vac 15 amp contacts and the wires to the plug arn't lined up...the green goes to the ground....just want it to be clear