Red Devil is pain in but for maintenance

[ACreque]

So i have a red devil male, in a 55 gallon, he's great and all, however i want a bottom feeder to help me clean up the tank, only problem is, he kills or eats everything that goes into the tank. Any suggestions, as to what i can do to help maintain the floor of the tank. He already killed a pleco, i do not need another. sigh. help, any suggestions will be greatly appreciated.

 

[Scottw68TN]

What kind of substrate? He'll probably kill anything that you put in. You can try snails but he'll probably pick at em till they die. My Oscar is they same way. I put sand in the tank and added MTS he seems to leave them be.