The City of Darwin council is considering buying a blanket for one of its pools, to stop it losing heat overnight and to keep swimmers happy.

The thermal blanket is expected to cost about $40,000.

Council figures show 70 per cent of regular local users stop going to Nightcliff Pool during cooler months, when the water gets as chilly as 19 degrees.

The Lord Mayor Katrina Fong Lim said water temperature had long been a hot topic for Darwin pool users.

"It's about acclimatisation, so people from ice-filled Scandinavia or something like that would obviously find it quite mild," Ms Fong Lim said.

"But, generally speaking, you're talking about people who are living in the tropics."

Ms Fong Lim said the council had "frequent" requests from within the community to warm the waters during the more wintry months.

"The thermal blanket ... it actually retains the heat from the day time in the pool and it raises the temperature by a couple of degrees," Ms Fong Lim said.

While it can get nippy during the dry season, council statistics show the temperature of Nightcliff Pool has a wet season average of 30 degrees and can hit as high as a soupy 33 degrees.

Council officers have advised elected members that a thermal blanket is a "much cheaper" option than solar heating.

They also said there was not enough roof space for solar panels.

The council is set to consider the recommendation at tomorrow's ordinary meeting.

Ms Fong Lim said this would be the first council pool to have such modifications made and that there were no plans as yet to make similar changes to the council's Casuarina and Parap pools.