Yep, I can understand that
, they swim straight into our hearts, they are too cute and my husband and I just LOVE them.
I cleaned our tank yeaterday, I do this once a week. I realised that after a week the glass starts to show a little algae growing, not all over but on a few spots. This is a sign for me to clean, but as I mentioned, I do it every week. And because we do not have a real big tank, it is a 34 l one with 2 comets about 7-8 cm, I change about 30% of the water and maintain a very good air circulation with an airstone which runs almost across the whole back of the tank.
And we watch our fishies closely, they do not show any discomfort at all, they seem to be "Happy as Larry"