A reg in the games I am playing in(6max) is opening 25% from utg. He is willing to 4b wider than AAxx when he suspect he is getting messed with. He mass table. 

How do I adjust to this loose utg range?

I think I remember Phil in one of his videos mentioning a similar situation and said that you don't need to adjust. By opening too wide he is going to be in -EV spots if you keep you ranges the same as if he were opening a tighter range. 

I feel I should be flatting more marginal hands on the button and floating and/or bluff raising more flops.

I don't know if I should be 3b a wider range. And if so what type of hand should I include? 

Thoughts