Unfortunately, a pond that small will not hold much in the way of wildlife. As others have said, a few smaller fish would be ideal but I would be hesitant to even do a couple of goldfish without a solid filtration system in place. That being said, the cycling process shouldn't hurt the fish, just keep an eye on them. Murky water is pretty typical for a while, but fish trying to jump out of the water is not.
And as mentioned above, you only need to add dechlorinator when you add more water.
And as mentioned above, you only need to add dechlorinator when you add more water.
