Ammonia: 0
Nitrite: 0
Nitrate: 2.5ish (between 0 and 5, only 2 days from my water change)
The tank is a 20 gallon SUPER heavily planted with five dwarf puffers (1 male, 4 female) and 3-4 ghost shrimp. It has a mix of life and fake plants. I feed once a day with black worms or pond snails, giving them a fasting day once a week. Water changes happen once a week on Thursday morning and I use Prime as my water conditioner. The tank is well established and has been fully cycled since October. I cycled fishless with ammonia and a bottle of QuickStart. There have been no changes in the tank in the last few months, let alone in the last week.
I have no idea what's going on with this little girl! My only thought is that she may have been picked on and harmed by one of the others, but they've been doing great for the last six months and rarely interact at all, let alone fight. Anyone have thoughts or advice? I don't have another cycled aquarium at the moment since I'm about to move so I'm at a bit of a loss on how I can help her.