The life span of a 'feeder' gold fish can be upwards of 30yrs and get to be around a foot long.... Some koi are listed in the 100s, no lie...... Koi can get to be over a yard long!!!!
No it is NOT true that fish will only get as big as the tank you put them in either... IF they live and you keep up good conditions with regular water changes and feedings, they will outgrow the tank and possibly become cripled from lack of space. Most just die before they ever get there....
*hehehe Something I know alot about..
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