But Mr Sherburn said that "naturally we won't be giving out any further details of the release places, but let's just say you won't catch one sitting at home!"
Anglers would know immediately if they caught one, as the green tags were prominent and the fish were healthy specimens around 35 to 45cm long, he said.
Numbers on the tags correspond to prizes contained in sealed and numbered envelopes, and one of them contains the grand prize of $10,000.
The other envelopes each contain a $200 tackle or voucher prize, "so every qualifying angler who returns with a Fish for Gold green tag will win a prize, even if it's not the big one."
Mr Sherburn said anglers and families who were planning to fish any of the three lakes from opening on were urged to "enter and have a go" as they had nothing to lose and entries were completely free.
"There's still time to enter as entries don't close until September 30 and although we are only accepting the first 1200 entries, we are still some way off that figure.
"Our hope is that Fish for Gold will stoke up the fun and excitement factor, and build some suspense around 'will I catch a 10k fish?'"
Mr Sherburn said that because the October 1 Opening Day fell on a Saturday Fish and Game expected a strong turnout of fishers, especially if the weather played ball.
"Our officers and helpers will be out in force as usual, and we traditionally talk to around 1000 anglers on the three most popular lakes - Tarawera, Rotoiti and Okataina".