Oh, sorry for the misunderstanding. I just meant that this is a very conservative aquarist community where the general consensus on a 4g is likely to be that it's too small.
There are plenty of fish that are appropriate for a 4g aquarium. like the 3 goldies pictured on the box.
In all seriousness, I wouldn't say that a small tank is ideal for a beginner, but I don't think it's so difficult if a sensible stock is decided.
I don't think the 2 fish initially listed as suggestions would be a bad choice for a tank this size, the extra volume offered by the filter and plumbing, and the heavy planting with fast growing plants (at least the hygro) should offset a good amount of the bioload. I don't think anyone ever accused an oto, or a couple of snails of crowding a tank.
my personal preference is for single species tanks, or largish schools rather than a single centerpiece, but there are hundreds of aquatic species that would do fine in a tank this size.
there are plenty of people selling nano fish, the vast majority of them will be happy to answer questions about them, including advice on what would work in your current setup.
but if you feel you can do it responsibly, give it a go!
