You said you pulled the waste gate and nothing happened. Can you tell if the gate opened? You can usually feel if there is pressure from the seals when you pull it so you know the rod is in fact hooked up or loose?
If connected there must be a blockage. Are you sure you actually are full? The meters usually don't read correctly.
Can you see into your tank from your toilet? Is it a straight shot or is there a bend in the pipe? Mine curves so I can't see into the tank. I was getting a blockage in the pipe so I bought a drain tornado from Harbor Freight. You hook it up to your hose and stick it down the toilet pipe and turn the water on. It will free up anything in it's way. Move it up and down the pipe all the way down into the tank. Clean as can be! Here is the link to the tornado.
http://www.harborfreight.com/drain-tornado-96850.html
Give us more information and we can probably help you.
Brian