Snorkelling Sardinia

Hello,
I was wondering if there was any half decent snorkelling in Sardinia? If so where? Is there any in the north? Is it worth taking my snorkel with me?
Thanks for any advice.

Could be, tho I haven't done it. The sea all around the island is sparklingly transparent, so I'm sure there are possibilities, tho obviously it's not the Red Sea or the Caribbean!