Reviews > Hydration Systems > Bottles > G. G. Aquatherm Bottle Insulator > Owner Review by Christopher Nicolai

GRANITE GEAR AQUATHERM WATER BOTTLE INSULATOR
BY CHRISTOPHER NICOLAI
OWNER REVIEW
November 06, 2006

TESTER INFORMATION

I have been backpacking for 10 years in locales from Chile to Alaska. I have experienced temps from -30 F (-34 C) to 100 F (38 C), heavy precipitation in virtually all forms, and winds exceeding 75 mph (120 km/h) - in everything from desert to rainforest to glaciated peaks. Most of my trips are 1-4 nights climbing/backpacking

PRODUCT INFORMATION

Manufacturer: Granite Gear
Year of Manufacture: 2004
Manufacturer's Website: http://www.granitegear.com/
MSRP: US$17 per Granite Gear website
Listed Weight: 4.3 oz (122 g) per Granite Gear website
Measured Weight: 4.7 oz (133 g)
Actual Measurements: 10" (25.4 cm) height x 5" (12.7 cm) diameter

Product Description
The Granite Gear Aquatherm is a closed-cell foam insulator designed to fit snugly around standard 1 qt (1 L) water bottles. Half-inch foam and a reflective insulation material are shaped into a cylinder with round pieces cut for the top and bottom and lined inside and out with a 210 denier nylon pack cloth for appearance and durability. The top lid has a pull tab and is attached with a 2" (5 cm) seam to allow it to flip open. A drawstring closure with a cord lock over the lid holds the contents secure when the lid is closed.

The 2004 model (and the current model per the website) has a 1.5" (3.8 cm) strip of hook & loop fastener running vertically on one side to allow attachment to a pack or hip belt. This strip is sewn at both the top and the bottom of the insulator. A Granite Gear representative confirmed that the Aquatherms are currently only manufactured in red.

FIELD USE

Primary Uses:
My primary uses for the Aquatherm are to keep fluids warm (or at least above freezing) while moving during the day and to prevent fluids from freezing overnight. I prefer to consume warmer fluids rather than colder fluids in low temperatures so that my body does not need to expend as much energy to heat the fluids to body temperature.

Secondary Uses:
I have found the product to excel at insulating hot drinks to keep them hot and cold drinks to keep them cold. I will often make hot tea before dinner, and it stays hot through the meal and still very warm through the campfire hours after dark. I sometimes use them on hot summer days around town when I am active outside to keep cold fluids chilled for hours. I have also used the insulators on occasion to protect semi-fragile items (i.e. camera lenses) during transport in my pack or luggage.

I have used the Granite Gear Aquatherms on many trips over the course of the past several years on backcountry trips in temperatures ranging from about -30 F (-34 C) to over 50 F (10 C). I have found the product to perform as advertised in a variety of conditions while standing up to years of hard use with only minimal signs of wear (slightly dirty but no loose stitching or rips). They have been subjected to snow, rain, & abrasive terrain in cold, Alaska and northern Minnesota winters, cool desert nights, and alpine climbing trips. I typically carry two 1 qt (1 L) water bottles in my Aquatherms anytime I am on a backpacking trip during which I expect temperatures may be near freezing or lower.

On one particular trip, I was out for six nights in Denali National Park in Alaska with overnight lows ranging between -22 F (-30 C) and -30 F (-34 C). Every night, I filled my water bottles with near boiling water, placed the bottles in my Aquatherms and buried them upside down under 12-18 inches (31-46 cm) of snow. Even ten hours later, less than half of the water had formed into ice. (Note that ice typically forms first on the upper surface of water. Keeping the bottles with the lid toward the ground helps prevent newly formed ice from blocking the opening of the bottle upon opening in the morning. Also note that due to potential leakage and loss of personal heat to the liquid throughout the night, my preference is to keep fluids outside of my sleeping bag.)

The Aquatherms fit perfectly into the water bottle pockets on the lower sides of my backpacks, which is where I typically carry them on a trip for easy access. The drawstring with the cord lock is easiest to use with two hands, but can be managed with just one hand if necessary. I don't personally use the hook & loop strip, but I have placed it over the hip belt on my backpack, and it seems to hold a full bottle securely. The strip is designed such that it could easily be secured to any straps on a pack with a carabiner or with a piece of webbing.

PRODUCT TESTING

Over the years, I have performed multiple controlled tests to determine the insulating properties of water bottle insulators. The Aquatherms have consistently retained heat more efficiently than other comparable insulators tested, which is a principal reason why I continue to use them. During my most recent test, I placed 32 oz (0.95 L) of pure water at 60 F (15.6 C) in a Lexan water bottle, secured in the Aquatherm and placed in a kitchen freezer with an average temperature of 0 F (-17.8 C). Every few hours, I recorded the amount of water remaining in liquid form. Following are the results for the Aquatherm showing the amount of fluid remaining after the number of hours shown:

6 hrs - 32 oz (0.95 L) fluid remaining (no ice yet formed)
12 hrs - 28 oz (0.83 L)
17.5 hrs - 24.5 oz (0.72 L)
22 hrs - 22.5 oz (0.67 L)

SUMMARY

The Granite Gear Aquatherm is a durable and effective insulator for fluids in extreme temperatures. It works better than anything else I've found to prevent fluids from freezing in cold temperatures - short of a thermos. While lightweight compared to comparable products or a thermos, each one is still over 4 oz (115 g) of weight to carry in addition to the extra bulk that accompanies the insulator. Therefore, I only carry them backpacking when I expect to encounter colder temperatures.

THINGS I LIKE

1) Effective insulator
2) Durable
3) Simple design with no zippers to fail

THINGS I DON'T LIKE

1) Available only in red
2) Weight
3) Bulk

Reviews > Hydration Systems > Bottles > G. G. Aquatherm Bottle Insulator > Owner Review by Christopher Nicolai