OK Im not a great feng shui expert.....my only exposure having been
minimal but if I understand the concept that the whole idea is about
creating balance and harmony and peace.....so puttting inappropriate
fish for the environment will negate this instantly......so you are
looking at creating the correct environment for your livestock, that is
peaceful and gives the right vibes/karma - am I right or wrong....stop
me here if I am off track.....
The goldfish/koi will not work but small tropicals might well
work....you will need a heater though to get the conditions
right....this can easily be hidden by clever planting.....now I would
say one of the best tanks that I have is a small 5 gall tank that is
lush with greenery and houses some tropical cherry barbs and shrimps -
all in that tank is balanced, peaceful and is a pleasure to look
at....if I was an advocate of feng shui then I would say that it has
been reached in this one small tank.....but JMO and I know very little
about the concept of feng shui
Gill