I worked for them. The e heater is to weak for the be use with 3W per gallon as usual or use with the nomber of gallons That they indicate on the product.
When it is not strong enough, Call the customer services and they Will send you a second one!(depend on your case, they'll ask question before but they're great with claims usualy.
The protector is there to protect the heater from fish!! Some poeple has big fish!! Like me!
If you remove the protection it Will be ok.