I have 26 neons in a 10g QT. They do not seem crowded. The neons will actually do better with a larger school.
If you don't feed the tank any more, there will not be any more biological load. The extra food you have to add for the four neons is how much more filtration you need. My guess is that this would be good for your tank, as long as you don't overfeed and stay up on water changes.
The only issue I see with your tank is 2x dwarf gourami in a 10g. If they haven't started fighting or breeding, they will, then everything else will be in danger.
Larger tank, more neons, or get rid of a gourami.
If you don't feed the tank any more, there will not be any more biological load. The extra food you have to add for the four neons is how much more filtration you need. My guess is that this would be good for your tank, as long as you don't overfeed and stay up on water changes.
The only issue I see with your tank is 2x dwarf gourami in a 10g. If they haven't started fighting or breeding, they will, then everything else will be in danger.
Larger tank, more neons, or get rid of a gourami.
