So I went to walmart when I bougjt my 29 gallon fish tank and I saw thwy had butterfly koi. The information thingy said they only get about 16 8nches in a fish tank but have the potenyial to grow big in ponds. Is this true? My science teacher has some in a 55 gallon. I don't wanna see any **** on "no, koI need a 1000 gallons"