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Exstream Water Purifier


From: Charles Lindsey, 7/30/99
Name of Gear: Exstream Water Purifier
Manufacturer: Exstream
Field weight: see below
Cost: US $39.95

Water Purifier

I recently received an Exstream water purifier to test from Exstream Water Technologies, Inc. Below is my preliminary assessment.

The Orinoco takes protection against water-borne varmits a step farther than mere water filters, in that it also protects against viruses. This is particularly important when traveling to foreign countries (especially to under-developed countries). We also received an Exstreme Orinoco for my daughter who will soon be traveling to Romania (where one should never drink tap water) to do some volunteer work. She will test it there, and when she returns -- alive and well -- we will update this review, accordingly.

I won't get into the Exstream Water Purifier's definition and specifications -- you can easily access that information at the Exstream website at

What I will share are my experiences to date, beginning with some factual/tested weights and comparisons, then continuing on with experiences and opinions.

Initially, I was disappointed with the weight of the Orinoco -- then I looked at the analysis below.

Empty/already primed: 9.7 ounces
Full to capacity: 31.2 ounces
Water capacity: 21.5 ounces

Exstream Orinoco, 9.7oz, 21.50oz water capacity, total weight full: 31.20oz
1 Liter Platypus, 0.9oz, 34.95oz water capacity, total weight full: 35.85oz
TOTAL WEIGHT FULL: 67.05oz (4.19lbs)

Exstream Orinoco, 9.7oz, 21.50oz water capacity, total weight full: 31.20oz
1/2 Liter Platypus, 0.8oz, 19.95oz water capacity, total weight full: 20.75oz
TOTAL WEIGHT FULL: 51.95oz (3.25lbs)

Exstream Orinoco, 9.7oz, 21.50oz water capacity, total weight full: 31.20oz
1 quart lexan Nalgene, 4.85oz, 37.50oz water capacity, total weight full: 42.35oz
TOTAL WEIGHT FULL: 73.55oz (4.60lbs)

Exstream Orinoco, 9.7oz, 21.50oz water capacity, total weight full: 31.20oz
1 pint lexan Nalgene, 3.00oz, 17.30oz water capacity, total weight full: 20.30oz
TOTAL WEIGHT FULL: 51.50oz (3.22lbs)

ORINOCO: 9.7oz, 21.50oz water capacity
PUR HIKER: 12.1oz, zero water capacity
1 pint lexan Nalgene, 3.00oz, 17.30oz water capacity
TOTAL: 15.1oz, 17.30oz water capacity
ORINOCO (1) provides 4.2oz more water capacity, (2) weighs 5.4oz less and (3) provides protection against viruses whereas the PUR Hiker does not.

ORINOCO: 9.7oz, 21.50oz water capacity
PUR HIKER: 12.1oz, zero water capacity
1/2 Liter Platypus, 0.8oz, 19.95oz water capacity
TOTAL: 12.9oz, 19.95oz water capacity
ORINOCO (1) provides 1.55oz more water capacity, (2) weighs 3.2oz less and (3) provides protection against viruses whereas the PUR Hiker does not.

The comparisons above could be extended out to include other types of water containers, filters and purifiers, but, clearly, the Exstream Purification System provides a potential weight reduction as well as a potential pack-gear-volume reduction, in that you don't need to carry a filter and/or purifier.

There are some unique aspects of the Orinoco that require that we actually read the instructions.
(1) the virustat cartridge has a protective, cover label that needs to be removed prior to using
(2) explanation of the system & its two filters and one virustat cartridge to include how the pre/post filter can be used as either a pre filter or a post filter depending on water conditions
(3) how to use it, maintain it, and store it properly

The Exstream water purifier has essentially a three filter system. The pre/post filter which can be installed either as a prefilter or post filter, depending on water conditions. Its function is to remove certain tastes and odors as well as sediment and organic contaminants in order to extend the life of the cyst filter. The 1-micron cystfilter removes more than 99.9% of pathogenic cysts, such as Giardia and Cryptosporidium. Finally, the ViruStat microbial water purification cartridge eliminates 99.9999% of waterborne bacteria and 99.99% of waterborne viruses.

I haven't used the water system long enough to comment on filter life expectancy, but the specs say the virustat system will treat up to 26 gallons of water. I would expect less than 26 gallons in less than ideal water conditions. So, conceivably, you might need to change the filters once or more during the course of the hiking season, as required. The entire purification system can be replaced for $29.95.


TASTE: The water tastes very good and clean. Even at home where the tap water tends to taste like iodine during the Summer months, the Exstream water purifier eliminated all water treatment tastes. I normally have a PUR home water filter hooked up to my tap water. The Orinoco produces results comparable to the PUR system.

PRIMING: It take a couple of bottles full of water cycled thru the Orinoco to get it flowing at top speed. When it first began flowing, the water was dark colored for a few seconds. The owner's guide indicates that this will happen. Apparently, it's just carbon dust that has collected and is being flushed out of the virustat cartridge.

DRINKING: The bottle must remain upright to ensure that the water passes thru the filters. Consequently, it took me a short time to get accustomed to the squeezing/sipping routine without slobbering on myself. Now, I am quite comfortable with the process. You're working against gravity here so the amount of water that you consume is directly proportional to the amount that your hand can squeeze out. Depending on how much you want to drink at any one time, you may notice tired hand muscles, but the hands get strenghened quickly and adjust accordingly. Also, you can use either hand or both hands for that matter. I didn't find it to be a problem.

THIRIST QUENCHING ? I found the flow rate / quantity available for consumption to be adequate.

CAPACITY: The Orinoco speeds up the process of collecting water. I use one 16oz Nalgene to scoop up the water -- literally on the run sometimes -- and on the way, when required, just transfer the water to the Orinoco. You could use the Orinoco as your sole water container or use it in tandem with other containers, depending on the duration of your trek and the available backcountry water.

(1) compared to water filters, the Orinoco adds water purification to eliminate viruses
(2) teaches you how to drink from a non-tilted bottle without slobbering all over yourself
(3) strengthens your hand and finger muscles which are required to squeeze the water out from the bottle

Insomuch as I have used it, I like it. I cannot yet comment on how it performs in glacial runoff and swampy water conditions, but in normal mountain water conditions, it does just fine.

In addition to lightweight backpackers, I would expect this product to also be attractive to backcountry runners.

Web: Water Filters & Purifiers

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