Fizz is not a good tank. But you don't need 1000 AP to be effective. The only hard thing about fizz is surviving in team fights after ur burst so u simply build healthy-ap. You can tower dive with ease. This build really shines when your team already does tons of damage.
All you need to do is kill 2 carries and your job is done. Every thing after that is a bonus... Watch out for Ryze, Kayle and Vlad. U may have to give up some minions. Don't be scared to back when you get to 6. U can kill many champs after one dorans ring if they underestimate you.

I like to max W then Q. I dont't max e because although it has great damage its a long CD andreally your Q and W do more reliable damage. The W is great for securing kills combined with ignite. Obviously get ulti whenever.

I'm not claiming to be pro. Just trying to share what i find. I'm no tabzz