Nice start! Although I don't see any fish in your pic, lol. Is that Eco Complete or Florite black substrate? I like a dark bottom...& black or dark background will make your fish & plants "pop" & hide equipment. You might lift up your dwarf sags a little, they seem planted a bit too deep. You want the "crown" (where leaves & roots meet) to be an ever so little bit above the substrate.
If you only EVER want to have neons & no other fish, I'd say you could, eventually, have say, 12 neons total. But, if you're lusting after a betta, or cherry shrimp, or whatever, in the long term then, no, not so many.
But you need to see what's happening with the "fat" neon & get your nitrites to zero before you add anything more. Patience is the hardest part of our hobby but often the most important. WAIT!
If you only EVER want to have neons & no other fish, I'd say you could, eventually, have say, 12 neons total. But, if you're lusting after a betta, or cherry shrimp, or whatever, in the long term then, no, not so many.
But you need to see what's happening with the "fat" neon & get your nitrites to zero before you add anything more. Patience is the hardest part of our hobby but often the most important. WAIT!