if i have water up to a good depth with many rocks can i put a few catfish in the tank.if not ofr if yes y?

Best not to.

2 reasons:

1 - turtles natural food is fish :-?

2 - turtles are messy animals, it's hard to keep the tank water clean enough for any fish thats big and tough enough to avoid being eaten in the first place.

Cheers

Ian

Yes you can I've seen plenty of catfish kept with turtles.

Fly River turtles that is...

There are many species of turtles kept in aquariums, and literally hundreds of different catfish from 2cm peaceful schooling community catfish to 3'+ predatory monsters.

It pays to give as much info as possible when asking questions.

I have a 300mm plecostomus with 3 adult turtles and they are all fine. They all started off as youngsters and grew up together. There are also some athletic guppies in there that are now about 4th generation.