Lagoon 50 unbelievable upgrades with John Pruim
In this Lagoon 50 review, John reflects on the reliability and liveaboard potential of his yacht Themis and the upgrades he has made to ensure this boat has the latest and greatest.
John Pruim is no stranger to the Lagoon lifestyle. As a four-time Lagoon owner and long-time client of TMG Yachts, John’s trust in both the brand and the team speaks volumes.
Now the proud owner of Themis, the first Lagoon 50 in Australia, John offers a firsthand review of the yacht’s spacious design and comfort at sea, and why he continues to choose TMG Yachts with every new adventure.
For anyone wanting to make upgrades to their boat and wondering what you can do to make your yacht self-sufficient, this tech-savvy Lagoon 50 owner is all about making this boat the best of the best with all the latest in technology…

Lagoon number 4
John is a dedicated Lagoon owner.
He describes himself as always wanting the latest technology moving from Mercedes to Lexus and soon to Tesla.
To him, Lagoon is the ideal unique cruising and sailing catamaran.
“Lagoon allows you to go from a to b safely, easily and reliably. There is a sense of comfort and space, perfect for being a house on the water…” Says John.
When sailing, things can go wrong from time to time, but John knows and trusts the exceptional build of Lagoons.
Self-sufficient
With solar covering the entire roof, this Lagoon is set with >3KW of solar power…
More energy can be generated with the upgraded engine alternators… Lagoons come with a standard 160AH with 80AH per engine but John has opted for 500AH with 250AH on both engines. Usually, the generator would need to run at least twice a day for a number of hrs to cover the energy requirements of this 50, which can be loud and use a lot of diesel.
This combined with four 360AH lithium batteries makes this the perfect boat to take off on and have no need to go back to a marina…


Why go lithium?
John admits that lithium is 2 to 2 and a half times the price of lead-acid batteries however they…
- are half the size
- are half the weight
- are almost double the capacity
- Exchange of power is much quicker and more efficient
- have a cycle range from 20% to 90% (whereas lead-acid batteries range from 50% to 90%)
- have 3000-5000 cycles lasting more than 10 years for the same AMP (whereas lead-acid batteries do 600-1000 cycles lasting 2-3 yrs.)
- same as full generator capacity
All these things lead to a more fuel efficient vessel
The latest and greatest
Being a 50ft vessel there is no limit in space so stocking up on the best equipment was no issue… This is what will be on board…
- Three fridges and a freezer
- Ice maker
- Water maker
- Dishwasher
- Washer and dryer
- Microwave oven
- Coffee machine
- Rice and bread maker
- Instruments
- Electric toilets
- LED lights throughout
- Power inverter
- 360-degree cameras for berthing
- Security alarm which records everything with motion sensors
- Alarm when bilge runs for more than 2 minutes
- Battery monitoring system from home
- Email notifications for where the boat is geofencing
- Wi-Fi/ data
- HF radio for the entire world

As a long-time client of TMG Yachts, John’s trust in the team speaks volumes. With nothing but positive things to say this is why John continues to work with TMG Yachts time and time again. “The team at TMG Yachts will work with you to ensure you get just the set-up you desire…” John Pruim



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