The mesh in the reptile hood I linked is easy peasy to cut. I made one hole big enough for the plug and snaked both filter cords and the heater cord through it.
You can also use Krylon Fusion Clear. I did that with a floating Betta log to keep it from peeling. But make sure it's Fusion. If colored, matte or shiny works. Shiny reflects better.
Oops, almost forgot: Get the clips and use on back half if you get the hinged hood.
If your dog thinks you are the greatest do not seek a second opinion