Mariah FS18 Fish & Ski 2006 boat specs
Mariah
Mariah FS18 Fish & Ski 2006
2006
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VS
Mariah FS20 Fish & Ski 2007 boat specs
Mariah
Mariah FS20 Fish & Ski 2007
2007
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Mariah FS18 Fish & Ski 2006 vs Mariah FS20 Fish & Ski 2007 — Same Brand, Different Boat

The Mariah FS18 Fish & Ski 2006 vs Mariah FS20 Fish & Ski 2007 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.

Size is the most obvious dividing line here. The Mariah FS18 Fish & Ski 2006 measures 18,0 feet overall (2006), giving it roughly 16,0 additional feet of deck space compared to the Mariah FS20 Fish & Ski 2007 at 2,0 feet (2007). Weight tells a clearer story for trailering families: the Mariah FS18 Fish & Ski 2006 tips the scales at 231 lbs — 198 lbs more than the Mariah FS20 Fish & Ski 2007 at 33 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.

The power gap is worth calling out. Rated to 260 hp, the Mariah FS20 Fish & Ski 2007 has a 70-hp advantage over the Mariah FS18 Fish & Ski 2006's 190-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Mariah FS20 Fish & Ski 2007 carries 38 gallons versus 22 gallons in the Mariah FS18 Fish & Ski 2006. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

For family outings this is probably the sharpest distinction between the two. The Mariah FS18 Fish & Ski 2006 is rated for 8 passengers, while the Mariah FS20 Fish & Ski 2007 caps at 1. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Mariah FS18 Fish & Ski 2006 could be the deciding factor.

At this size, power-to-weight ratio matters more than outright horsepower. The Mariah FS20 Fish & Ski 2007 comes in at 0 lbs per hp versus 1 lbs per hp for the Mariah FS18 Fish & Ski 2006. The lower the ratio the more explosive the acceleration — meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.

Bottom line: Choose the Mariah FS18 Fish & Ski 2006 if your priority is putting more people on the water — it handles 8 passengers and at 18,0 ft it has the deck room to back that rating up comfortably. The Mariah FS20 Fish & Ski 2007 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 1 that costs less to run day-to-day.
General Boat Info
MakeMariah
MakeMariah
ModelFS18 Fish & Ski
ModelFS20 Fish & Ski
Model Year2006
Model Year2007
Measurements / Dimensions
Beam7 ft. 8 in. (2.3 m)
Beam8 ft. 2 in. (2.5 m)
Beam - Meters2.34
Beam - Meters2.49
Beam - Inches92
Beam - Inches98
Deadrise18℃
Deadrise19℃
Weight - Detail2,310 lbs. (1,048 kg)
Weight - Detail3,300 lbs. (1,498 kg)
Weight - kg1047.8
Weight - kg1496.85
Weight - lbs.231
Weight - lbs.33
Length - Meters5.5
Length - Meters6.1
Length - Feet18
Length - Feet2
Length overall - Detail18 ft. 0 in. (5.5 m)
Length overall - Detail20 ft. 0 in. (6.1 m)
Length overall - Meters5.49
Length overall - Meters6.1
Length overall - Inches216
Length overall - Inches24
Engine and Drivetrain
Fuel tank capacity - Detail22 gal. (83 l)
Fuel tank capacity - Detail38 gal. (144 l)
Fuel tank capacity - Liters83.28
Fuel tank capacity - Liters143.85
Fuel tank capacity - Gal22
Fuel tank capacity - Gal38
Fuel typeGas
Fuel typeGas
Drive typeI/O
Drive typeI/O
Engine max190 hp (142 kW)
Engine max260 hp (194 kW)
Operational Info
Maximum capacity1,250 lbs. (567 kg)
Maximum capacityPerson: 1,590 lbs. (721 kg) Total: 3,550 lbs. (1,612 kg)
Maximum people8
Maximum people1
Body / Hull
Hull materialnot available
Hull materialFiberglass

Mariah FS18 Fish & Ski 2006 vs Mariah FS20 Fish & Ski 2007 — Common Questions

Which is the larger boat — the Mariah FS18 Fish & Ski 2006 or the Mariah FS20 Fish & Ski 2007?
The Mariah FS18 Fish & Ski 2006 is the longer of the two at 18,0 feet overall. The Mariah FS20 Fish & Ski 2007 comes in at 2,0 feet, making it roughly 16,0 ft shorter — a meaningful difference in deck room and overall on-water presence.
Which is easier to trailer — the Mariah FS18 Fish & Ski 2006 or the Mariah FS20 Fish & Ski 2007?
For trailering, the Mariah FS20 Fish & Ski 2007 has the edge at 33 lbs dry weight versus 231 lbs for the Mariah FS18 Fish & Ski 2006. Add a motor (typically 300–500 lbs for an outboard in this class), gear, and a partial fuel load and the difference grows. Lighter is friendlier on smaller tow vehicles and on fuel economy while hauling.
Which boat can handle a bigger outboard?
The Mariah FS20 Fish & Ski 2007 is rated to a maximum of 260 hp, giving it the larger power ceiling. The Mariah FS18 Fish & Ski 2006 tops out at 190 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.
How many people can each boat hold?
The Mariah FS18 Fish & Ski 2006 is Coast Guard rated for 8 passengers, while the Mariah FS20 Fish & Ski 2007 is certified for 1. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.
Which boat has the better power-to-weight ratio?
The Mariah FS20 Fish & Ski 2007 has a better power-to-weight ratio at 0 lbs per hp compared to 1 lbs per hp for the Mariah FS18 Fish & Ski 2006. A lower number means quicker acceleration and faster time to plane — the number that actually matters most on short, sporty boats like these.
Which boat is wider, and does it affect trailering?
The Mariah FS20 Fish & Ski 2007 measures 98" wide, compared to 92" for the Mariah FS18 Fish & Ski 2006. The US standard-width towing limit is 8’6" (102") in most states — anything over that may need a wide-load permit. Confirm your specific route requirements with each state's DOT.
Which boat has the larger fuel tank — the Mariah FS18 Fish & Ski 2006 or the Mariah FS20 Fish & Ski 2007?
The Mariah FS20 Fish & Ski 2007 has the bigger tank at 38 gallons, versus 22 gallons on the Mariah FS18 Fish & Ski 2006. That 16-gallon difference translates to roughly 48–80 nautical miles of additional range at cruising speed, depending on motor, load, and conditions.
Are the Mariah FS18 Fish & Ski 2006 and Mariah FS20 Fish & Ski 2007 from the same manufacturer?
Yes — both the Mariah FS18 Fish & Ski 2006 and the Mariah FS20 Fish & Ski 2007 are built by Mariah. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.