Wave maker using Windshield Wiper delay relay?

I'm an auto tech and I think Dyngoe idea will work...

If you use the delay module and the wiper switch (Not the wiper motor itself) and a relay for the 110 ac v. PH.

You should be able to choose your delay speed via the wiper switch then the module would pulse the relay and in turn pulse the PH.

You could also automatically alternate between 2 PH while one is off the other would be on. It could be done with a 5 pin relay...

The only part I'm not sure about is putting 110 ac V. thru a relay.... who knows what kind of arc will be going on in there...

You know, that's why I wounder why do they make 110 ac v PH and heater's when DC motors and such are so much safer...

Are there any DC powered PH made out there ? Wouldn't it be nice knowing that there isn't any deadly AC current in your tank? If the power went out you can still have flow and temp control simply be hooking up a regular car battery or a jump pack.