New 5 gallon bowl

Question
Hi Stephanie,
I was recently in China and was gifted a gorgeous ming dynesty 5 gallon bowl. The person who  gave me the gift has a similar bowl and had kept koi's in it. He had live plants too and had about 2 - 3 koi's in there. He claims he never changes the water and the fish looked pretty healthy to me. He has had these fish for over a year now and none of them died. He had no filter nor an oxygen pump in the bowl but the opening of the bowl is wide....so he claims they get oxygen from there...
I am very very keen to keep fish in my bowl too... but will not be able to replace 5 gallons of water every week as I have to use bottled water for my tanks ( i already have 2) the water where I live has been trated and the fish die in it.... so changing the water every week will be very expensive!
Also, the place where I can put the bowl has no electricity connection so putting a filter and pump is not possible... i would have to ahve wires running across my apartment if I wanted to do that....
what can i do!! ? help!!!!
If you think koi's are not a good option, what other fish could I keep? The bowl is dark green so the fish would have to have a good colour so that I can see them....
Hope t hear from you soon

Answer
Hello,

I think kois or goldfish are a fine idea for you bowl. I would not recommend live plants though, because they require a lot of sunlight and often artificial UV lights, which would need to be plugged in.

You would not need to replace the 5 gallons each week, but you do need to change some of it. Your friend is very lucky that his tank has not had any problems, but most tanks require water changes to stay healthy. What is added to your local water that makes it unsuited for your aquarium? If it is chlorine or chloramine you can buy tap water conditoners to neutralize it. These chemcals are much cheaper then adding bottled water!

You do not need a filter. Although an air pump is advisable, it is not a necessity. Your friend is right in saying that your fish can get oxygen just from the amount that dissolves at the surface of the water.

I hope this helps and that I didn't miss anything.

Regards,
Stephanie