How long to cook seafood in paella? This recipe for seafood paella says to add mussels, prawns, squid and monkfish to the paella pan 5 minutes before finishing, stir and then cover with a lid.

I made this twice and I have never been able to cook the seafood in 5 minutes. The mussels will still be closed, and prawns doesn't look red throughout. On the second try, I let it cook a bit longer and overcooked the seafood, which shrunk into a very small size.

How can I tell if the seafood is done? How long do I generally have to cook seafood for in a covered paella dish?
When I make a paella I never cover it, I find it keeps in too much moisture. My uncovered method is to put the fish in and cook for 10 minutes. If my mussels are small I will usually wait 2-3 minutes before putting them in, bu for "standard" mussels 10 minutes seems to work well. I use a low-medium heat on a large burner.