Does the koi fish need to be up or down?

Koi Carp are very large fish growing to over 24 inches. They should be kept in ponds outdoors not in fish tanks. All fish produce ammonia (including Koi) so all fish need their water filtered to remove this poison.The basic rules for successfull fishkeeping are. 1 inch of fish needs at least 1 gallon of water (A Koi is a 24inch fish) :- Every tank must have a permanently running 'cycled' filter. Every tank must have at least 50% of its water replaced every week. If you follow the above rules your fish will stand a reasonable chance of surviving. If you don't, then I can guarantee that your fish will be constantly getting sick and will die much sooner than it should.