u/Thatfish08

It’s been over 7.5 months with my tank.
Currently I have 1 betta fish, 1 nederite snail and 2 African dwarf frogs.
So many changes over the time but still managed to keep it up going.
When does an aquarium can consider mature?

Hey this is my Betta splendens male type plakat marble koi
I read that they might change color, is there a reason?, can I expect it to happen?