Turn a shader on and off

[Fienyx]

I'm trying to make a spell, which I have done plenty of before. This spell is different than anything I've done though. All I want is to be able to have a particular shader turn on then off after a second or so. I've never done anything with shaders and am find only less than helpful stuff through google.  The shader I want to use comes from NightEye Shader Replacement, which I already use for my nighteye. My default nighteye is the green, but the spell I want to make uses the edge detect, and I want to call it Sonar. 

 

How can I get a spell to use this shader.. just to turn it on then off.

 

EdgeDetectPSO.7z