Although the lodge is full, you don't ever get the sense you're sharing the quiet gardens with anyone else. People tend to keep to themselves and everyone has a special outdoor area for privacy.
Ken arrives and suits me up with waders.
Unfortunately, fly-fishing isn't suitable for under-8-year-olds so I guiltily set the kids up with a craft activity to make their own magnetic fishing game before leaving them with their dad for a few hours in the hope of catching some trout to smoke for our dinner.
Walking to the river through clear pathways fringed with wild blackberry bushes, I ask Ken how many trout we will catch and the best ways to smoke it later that night.
He laughs gently. "If you want to catch fish, go to the ocean. Fly-fishing is all about going slow, it's about learning about life and the people you meet on the way. You'll notice how aquatic life changes with the seasons and experience the beauty around you."
I'm starting to get my mindset into fly-fishing now. It's a thoughtful sport that attracts people who seem to like working out the puzzle of it, something it would take a lifetime to master.
Despite the forecast, the sun is brighter than it has been in months as I hold hands with Ken and a lawyer from Auckland, Brett Rawlings, who stays at Creel Lodge a couple of times a year with his parents and grandparents to fly-fish. We navigate fast-flowing water up to our waists.
Crossing to the sandbar covered in large pebbles with pumice floating around the edges, I put my foot down and a large trout wobbles around beside it.
"You're a fish magnet," says Ken, who recently guided some Japanese businessmen who hadn't been outside for a whole year because of fear of radiation. It feels good to have this beauty on our doorstep and fly-fishing must be one of the best ways to appreciate it.
Although I didn't manage to get a fish on my line, it didn't really matter - trying to master the casting and learning about the different types of flies, without getting carried down the river, was enough for a beginner.
Others had more luck. I watched anglers down-river huddled over nets catching and releasing their fish and, right at the end, Brett caught a rainbow trout that he carefully released again.
Back at Creel Lodge, the kids have mastered their own "fishing" and our son catches a paper fish, exclaiming, "This one is too small, I'm throwing it back in." It seems he's learnt a lesson about fishing already, just by listening to our conversations.
On the way back to Auckland, we stop at the Huka Prawn Park just north of Taupo and the kids finally get a chance at "real" fishing.
Our son catches a prawn almost immediately as onlookers in deckchairs look up from their Kindles and couples dipping toes in the water smile at him, while they wait for their own lines to pull.
With its fishing, treasure hunt, foot bath, tree climb and playground, the Huka Prawn Park was the perfect entry-level fishing experience for the kids and we're glad we had a quick detour to find this spot. On the way out, we pass a pole with PUSH in large letters and "don't" in small letters. We push. A jet of water hits me in the face.
It's a million miles from the experience earlier in the day on the Tongariro River, with its autumn leaves, blackberries and natural beauty - but, one day, this "learner pool" will inspire the kids to lead us back to the beautiful Tongariro for a family fish.
GONE FISHIN'
Creel Lodge: 183 Taupahi Rd, Turangi/Tongariro. Phone: 0800 273 355.
Ken Drummond Fly Fishing Adventures: Phone (07) 386 0411.
Fishing for kids: The Tongariro National Trout Centre holds kids' fishing days throughout the year. Bookings essential.