However, Kent Jarman, the Mount Maunganui surf lifeguard heading the search, said they would continue to search during the weekend.
"We have given the family an obligation to do the best for them. We will carry on for the weekend and review on Sunday.
"Ultimately we have to be realistic, [Saturday] will be 10 days, after that there will be diminishing chances of finding him."
Mr Jarman said they had been able to cover all the rocky areas around Motoriki, Rabbit Island, the inner Tauranga Harbour and an 8km to 10km search up Matakana Island.
"We haven't lost sight of the fact that you can do a search one day and the conditions change completely. You have to keep covering the ground you have covered before ...
"In previous cases it hasn't been us that has found somebody, it has been a member of the public. The more eyes looking for Jack the better."