Celebrity couple Darren Lim and Evelyn Tan lived on their boat with their four children for four years, moving back to land only in 2016 so their eldest child Kristen could prepare for the Primary School Leaving Examination.

But the sea still beckons. So, when their daughter turns 20 in five years, the couple plan to move back to a boat, but it will just be the two of them.

Then, Lim says, Kristen will be old enough to take care of the household on land. Today, the family calls a condominium in Upper Changi home.

Lim's passion for sailing turned into a steady stream of revenue when Covid-19 scuppered his filming gigs that would have taken him to countries such as Rwanda and Egypt.

The 48-year-old actor-host's 500 sq ft, three-room Lagoon 400S2 catamaran is among the boats for charter at Ximula Sail, which has seen a surge in demand during the pandemic.

Charters are fully booked almost every weekend till the end of the year.

Lim, who has been a co-owner and director of the company since 2017, says: "The circuit breaker was the longest period of my adult life that I'd been stuck at home - I didn't travel for more than two months."

On the filming front, things are slowly picking up, says Lim, who joined show business in the mid-1990s and has acted in dramas like The Little Nyonya (2008). He is now working on a Mandarin show, Fixer, which spotlights social issues.

While his overseas work is still grounded, he is bringing in income at sea.

Ximula Sail offers experiences - such as a four-hour trip (from $1,000+) to the Southern islands; and a three-day, two-night sailing holiday ($7,500+) to Pulau Hantu, Lazarus Island, Pulau Ubin and Seletar Island areas. The boats are captained by various people, including Lim when his schedule permits.

"Acting is my job, but boating is my life," Lim says, speaking to The Sunday Times on board his catamaran, named Gracefully, at the One15 Marina in Sentosa Cove.

In the meantime, his 46-year-old wife, who has a mathematics degree from the National University of Singapore, homeschools their three eldest children.

Kristen, 15, and Jairus, 13, follow a homeschooling curriculum called Classical Conversations, which imparts a Christian worldview, and are working towards getting their high school diploma, which is equivalent to an A-level certificate.

Jairus and Way, 11, have dyslexia. Because they require more attention, the youngest - seven-year-old Elliott - goes to a mainstream primary school.

It has not been easy, Tan admits.

"Sometimes our expectations can turn into burdens for people who are wired differently.

"I constantly have that struggle: Am I pushing them hard enough? When is it too much, and when do I step back and say, that's okay, because you've done your best?"

She completed a course at the Dyslexia Association of Singapore where she learnt about the Orton-Gillingham approach, which is designed to help struggling readers.

Homeschooling does not mean no tuition. The three eldest children attend Mandarin enrichment classes.

Tan, now a part-time artiste, concedes: "When we speak to them in 'Channel 8', it comes back in 'Channel 5'."

While their kids' education is a priority now, a life on the water remains at the back of the couple's minds.

Lim's love for the sea runs deep. He learnt to scuba dive in his teens, and, in his mid-20s, bought his first boat off eBay - an $800 dinghy with an outboard motor. It was so old, he recalls, that it oozed "juices" and fell apart after two years.

His second boat, Ivy And Ah Hock, was named after the lovebirds he and Tan played in the 1998 television adaptation of Dick Lee and Michael Chiang's musical Beauty World. The couple wed in 2004.

Living on the water has always been Lim's dream. It took him 10 years to convince Tan to take the plunge. She was worried about the potential dangers. What if the kids fell overboard?

But Lim persisted.

"Every night, I would be on the Internet, showing her what other people were doing - some were homeschooling (their children) while sailing around the world."

In mid-2011, they moved into a two-room Beneteau Oceanis 37 monohull, where they lived for 11 months before upgrading to their present boat, which cost $700,000.

They rented out their condo when they were on the boat, which was docked in Sentosa most of the time, but also sailed to neighbouring countries.

The children - Tan gave birth to Elliott in November 2013 - learnt to take responsibility for their own safety.

Lim says: "I told them, if you fall overboard, especially on a stormy night, the chances of me saving you are zero. I've had nightmares about such accidents."

He recalls a big storm in the Gulf of Thailand: "It happened in less than a minute - from zero wind to 160kmh and I had never seen such black thunderclouds before."

Tan, who used to get seasick often before she found her sea legs,says her husband's zest for pursuing his passion is partly what attracted her to him in the first place.

"Sometimes I think I forget to play," she says with a laugh.

"I married someone who knew how to play and takes me along on his adventures."

It took Lim - Tan calls him an "amphibian" - more than six months to get used to life on land again. "I literally had sleepless nights," he says.

And he pines for the life at sea.

"My kids can stay in the house, and I'll leave with my wife. They will look after themselves and be independent," he says of his future plans.

But what does Kristen think about her parents' intentions to take off without them?

"It's an interesting prospect," she says with a laugh.

"I do love my brothers and love to spend time with them. So being together in a household, possibly without our parents, we can make that work."