"Today [Tuesday], the life supports were removed in order to let Te Ariki die peacefully as he was unable to survive the unrecoverable situation," the page said.
Police said they were called to the incident at 4.30pm on Sunday.
"One person was transported to hospital in a critical condition. However, they have since sadly died. The matter is not suspicious and has been referred to the Coroner."
Te Ariki's Givealittle page had been set up to fundraise for his funeral costs after the "tragic accident".
"Lee is a solo mum with five children and at this difficult time of year she requires any support that you're able to give to enable Te Ariki to have a fitting ceremony to celebrate his short life," the page said.
"If you're able to give a donation, however big or small, it would be greatly appreciated. This is a tragic loss for the family."
The page had raised $5300 by this afternoon.
A death notice posted for Te Ariki described him as a "loved and treasured" son.
Te Ariki is the second toddler to drown in Christchurch in recent months.
Oliver Bailey, 2, died in a pond at his Linwood home in September after being found floating in the water by his mother.