So I am planning to set up a tank but I just wanted to make sure I don't fill it up too much. I have previously had a 10 gallon tank with a betta, 4 otocinclus catfish (I know I should have had at least 6 but I was planning on giving them away soon to a friend who already had some so that's why I just had the 4), and 2 mystery snails. The tank felt a bit crowded at times but luckily my betta, Raven, was the chillest dude ever and didn't mess with anyone. For this new tank, I am planning to use a 20 gallon tank, with a betta, at least 6 corydoras (never had them before but heard they work well with bettas), and at least 2 nerite snails. I was just wondering, does this tank sound too crowded? Or should this be a good amount? I am planning to have a planted tank with plenty of space for hiding and as bettas and corydoras tend to be areas of the tank (the top vs. the bottom respectively), I was thinking that this should be fine? If there are any issues, any advice is welcome. I'd rather have too much space for the time being rather than too little ad have to get rid of anyone due to problems arising.