My first thought is egg crate with either screen or a large piece of crochet canvas over that, to reduce the size of the crate holes. Under that you could use a cheap wash basin, sterilite container, etc. as a catch. Make it either removable, or add a bulkhead for easy drainage, although removable would be easier to clean/sterilize. Keep in mind I'm a newb, I'm sure other, more experienced individuals will come along with better ideas.
Then again, at the top of this forum, there's a sticky with drainage ideas!