Suck out as much of that as you can. It is decaying. Once the bacteria multiplies enough, they will get to it but it is causing issues in the current time.
You just need to wait for things to clear up, the ammonia to back down to zero.
When you start back up, just realize that cycles are never done. These things are cyclical and ongoing. New additions take time for the tank to ramp up and change with this cycle. The whole danger of people saying that tanks are cycled is dangerous for these reasons - people think that they have somehow turned a corner or that things are done when all that happened is that you have enough of a base to slowly, smartly and cautiously progress a bit. It is better to use more appropriate descriptions and terms like you are creating an ecosystem so don't go too fast to where it cannot keep up.
The bacteria will build up (grow in numbers) while clearing up this event. It will be easier next time, but please go very, very slow and be patient.
