My first saltwater tank.

[tyro]

Got up today and did some testing. Ammonia was a 1.0..... nitrite 0 nitrate 5. I did some research trying to find out how much ammonia is dangerous to fish etc. And found out there are a lot of false reads and inaccuracies with using this method. The tank doesn't smell, its not cloudy. Water has a slight green tint in my opinion. Likely algae from the before. I was due for a 10 pct water change so I did that and retested out of curiosity. Showed a .5. I'd love some opinions on what to do if anything. I do have prime and an ammonia treatment on hand. I'll include some pics. My nem actually looks like it has some purple forming at its tips. The mushrooms are all open. Kind of curious though the biggest one is in like a flower shape. Is that something they normally do? And the last coral can someone verify if that's a type of goni? Or even maybe what kind.