Neon tank size is a debatable thing. Fish stocking breaks down into bioload and swimming space. Your tank has enough bioload space for neon tetras- which is sort of a hard number and not really debatable. Swimming space is a lot more arguable- and people have different opinions of what constitutes acceptable swimming space.
I tend to agree that a 10 gallon is a minimum for neons, and some would say even larger than that, as they are fairly active.
You could always look into ember tetras, which are small and beautiful! A betta would also work- probably your best option.
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Loach count: 21
Baby fish count: 700+ (shelldwellers, gbr, angelfish)