Hi!
The other day I found a very simple and safe way to switch high power mains using a wireless transmitter and a receiver that I'd like to share.
No signal coding is required and no need to break up a remote control.
I posted a clip on youtube of how an off the shelf nexa transmitter and a relay hooked up to the arduino can switch 220v and probably also 110v. I am shure I am not the first to do this, but since I have looked for similar solutions for a while I thought it valuable enough to share.
Hope this can help other people like me that don't like to fool around with high power cords.
After finding this out I could immediately complete my ph controller, where the arduino controls a 220v solenoid for CO2 supply to my aquatank.
I am very grateful to this community for all the information that is provided on this forum. Without it I would still be blinking leds via pin 13 
Cheers!