I am replacing the wall to wall carpet in my house and need some help!

The carpet that you see in the picture was there when we moved in. While it would not be my first choice in terms of aesthetic (color or feel), it has been kind of brilliant in terms of performance. This house is on a beach and we have small children and a dog -- and this carpet is fabulous for hiding all the wet, sand, mud, food spills, throw up.. Plus, it's a pretty thick pile and is comfy and warm, which has been because we spend a lot of time on the floor.

I'm replacing it now and don't know how to think about good options. Things that are important to me are:

--Non-toxic (as I said, we have lots of little children)

--Hides sand, dirt, spills etc. Can handle being wet. I do not want to stress about this carpet.

--Comfortable

--Hardwood floors are not an option

Thanks in advance for the advice!