The session starts at 6pm at the Waterski Club end of the lake. There will be kayak support for those swimming and novice swimmers can swim along the shore line in the passive lane if they don't want to go out too deep.
Rats holds fortnightly aquathons - a swim followed by a run - aimed at adults and children. The alternate Mondays are an open water swim session for members to swim as far as they wish.
It is about 1.5km to the far end of the passive lane.
The club runs a variety of training sessions and events throughout the year, including club championships in both triathlon and multisport, Christmas function, club lunches at well-attended events and run clinics.
"If you have a question but have been too afraid to ask before, then this is your opportunity," Dobson said.
"You can have a quiet chat with any of the members who will be there and they will be happy to share any tips, and negate any fears. We have all been new to triathlon."
The Beginners Night is at Tikitapu (Blue Lake) on Monday, November 19 from 6pm.