Ottodita,

You can use that rod for trout. I used an 8wt rod on trout for a while because it was the only 9' rod I had. I cast flies as small as #22 using that rod, and caught some nice trout.

I also have a whippy inexpensive 6wt similar to what you describe. When I switched from the $6 line I had on it to a decent fly line, it was like magic. Suddenly I could cast, and even enjoy casting.

Years later I can now cast a cheap line without a struggle, but it sure made a big difference for me when I was learning to cast.

Regards,
Tracy