There are websites with calculations about how many fish you can host in an aquarium, how much water changes you should make, etc. I have a 60 gallon tank with 15 African cichlids(few haps, most peacocks). They are some full adults, and other big juveniles. This tank gets 50% water changes every week. But I feel at this point it should get two water changes during the week instead of one. The water quality looks not as pristine or sparkle clean(but it’s not too bad neither) as another tank where I keep south american cichlids, cyprinids and tetras all together.
Haps need more space now. So a 150 gallon tank is what I aim at by the end of the year
I know people who keep fish extremely overstocked in a fish tank and never do water changes in weeks. I don’t know how the fish are able to survive, but I’m sure if those fish would talk for sure will say “I hate you.”
When I started with fish tanks almost two years ago I had lots of questions about how many fish was going to be enough in an aquarium? (a general rule of thumb is an inch of fish per one gallon of water). What filters to use? Are those filters able to sustain enough bacteria to keep the fish alive?, etc.
Overtime a lot of myths were that “myths”. But overstocking common tropical fish(tetras, barbs, etc) is not the same as overstocking cichlids. You have to real life live it to make your own opinion. That comes after you experience a lot of fish in your mileage.