your tank looks like its good (not understocked, but not overstocked)
except for the pleco
i would get 3 more neon tetras, as they are schooling fish and even when they don't school, they feel more secure with their own species
as for the pleco, i know you love him/her to bits but if you do you will give it away
pleco's get 12" and i have seen them this big plenty of times
they need at LEAST 55 gallon (since they are not very active then this is the bear minimum they can live in) but are ideal for 70 gallons+
he will become stunted in your tank
which means you will see him start to look deformed as his insides continue to grow and his body does not (to compensate for lack of space)
sorry to be so graphic but it is important you know the details for your pleco's sake
if yours is tiny it is because it is just a baby
better take it back now before you get too attatched
