So I've read through several other threads here that talk about a urine smell and none of them really describe what I'm experiencing. The smell is coming from inside the toilet bowl. As in, you can't smell it at all until you lift the lid, and when you shut the lid again, the smell goes away. It's always there, even if it hasn't been flushed and it's just clean water sitting in the bowl. The toilet is firmly in place and sealed properly. There's no odor around the base of the toilet or the tank or anything. It's only coming from within the bowl and it's all the time. Any idea what this could be?