Hello there nice to meet you all! I'm new here and I would like to ask you guys something. I have 100litr aquarium with some plants and I have 10 albino corydoras, 7 female bettas (not sisters, still doing great almost a year now) 3 apple snails and some rahmson snails. And I was talking with a friend who once was in the hobby too, and he told me that a could put some more fish in the tank. Some cardinals maybe or a school fish in general. I have the external filter dophin astro 2208. What do you think is that okay to do? If so, what fish you would add? Sorry for my English I'm from Greece and I'm not that familiar with the language. Thank you.