Field Report: AquaStar Plus Water Purifier
Date: November 23rd, 2005 Manufacturer Name: Meridian Design, Inc. Website: http://uvaquastar.com	Product Information Manufacturer: Meridian Design, Inc. Model: AquaStar Plus Year of Manufacture: 2005 Capacity: 32 oz  (1 L) MSRP: $95.00 (US) Listed Weight: 8.5 oz  (240 g ) Measured Weights:        Control head/UV Tube 2.6 oz  (74 g)       Batteries (pair) 1.1 oz  (31 g)       1 L Polycarbonate bottle 4.2 oz  (119 g)       Total  8.0 oz  (227 g)

Tester Information & Background

Name: Andy Rad

Gender: Male

Age: 48

Height: 6 ft (1.83 m)

Weight: 165 lb (75 kg)

Email: aisrad@cableone.net

I started backpacking 21 years ago, most were short three-day trips, but are now generally five-day.  By backpacking, I’m referring to summer, winter camping, and fall hunting.  About half my trips are lightweight solo and the other half with my family.  I used to own a llama, thus allowing me to continue backpacking with my small children.  In recent years I’ve substituted a collie for the llama. When I’m not with the family I tend to take less-traveled trails or bushwhack the hard mountainous terrain in and around Idaho.  The majority of my trips are in central Idaho, with a few into northern Idaho, eastern Idaho, and eastern Oregon.

Field Report

My AquaStar UV water purifier has purified many gallons of water over the last two months.  My hiking partners just shake their heads when we hit a lake/stream and I have purified water with no work, nor waiting 30 minutes for chemicals to work.  I have become the water boy, as I now fill their jugs as well. The convenience of arriving at a water site and having ready to drink purified water in under 2 minutes is great.  But, this is not to say there haven’t been a few issues with this unit.

For starters it quickly became apparent that the generic factory supplied lithium batteries were deficient at low temperatures.  When temperatures drop to around freezing the unit would not complete a successful water purification cycle.  Instead of cycling for 90 seconds and ending with a successful green LED status, the unit might cycle for 20 seconds and end with a red LED fault.  Not knowing what the issue was I tried warming the water on my stove, but found that didn’t help.  Fortunately I had a fresh set of Panasonic batteries and the unit preformed ok with the new batteries.  The following afternoon as temperatures warmed, I reinserted the generic factory batteries and they worked once again.  Considering that lithium batteries are the best performing cold weather batteries, I was surprised that brand name batteries were substantially better.

I validated this at home by putting the unit in my freezer and dropped the temperature to 10 F (-12 C).  I found that the unit worked OK with Panasonic batteries, but the generic factory supplied batteries had to be warmed.  Testing indicates that the electronics of the unit are capable of working in sub freezing temperatures, but generic/cheap batteries are unreliable at sub freezing.  This is an issue for late fall backcountry, where the temperatures go below freezing during the night, but where water source temperatures are well above freezing.  I just make sure and drain the unit at night or sleep with it to keep water from freezing and breaking the unit.

During the following backcountry trip the unit worked ok the first day, but the next morning it was intermittent, and then stopped working all together.  I observed moisture in the test head and a crack in the ABS plastic housing that originated at the Quartz UV tube to ABS plastic joint (see photo below, above the Philips logo).  I suspected it was caused by either the cold temperatures of my freezer from previous testing or the 14F (-10C) from the night before.  I contacted the manufacturer and they ran several units through freezing test cycles and were not able to recreate, but did indicate that they had opened up the ABS plastic joint due to an overly tight fit during assembly.  I can only surmise that the temperature coefficient differential between the ABS plastic and Quartz UV tube caused the stressed joint to crack, but that's just my guess.  Either way, the plastic mold has been modified to alleviate this from happening on new production.  In the mean time, I dried the unit out by leaving the battery cover off, and glued the crack with “Marine GOOP”.  It has been working fine ever since.

The manufacturer immediately offered to send a replacement, but indicated that if I waited a few weeks, I could test their new release.  The replacement will have four changes to remedy issues and improve functionality.  The first is a modified ABS plastic to Quartz UV tube modification to eliminate the possibility of cracking at freezing temperatures.  The second is retooled threading on the cap so it will fit their bottle as well as Nalgene bottles.  The third is that the blue plastic wire guide next to the UV tube has been replaced with a glow in the dark piece. The forth is an improved end of cycle indicator. 

I am pleased that the manufacturer listened to our test group about the difficulty in observing the green/red LED test cycle indicator in sunlight.  They have taken the lantern LED feature and incorporated it into the test cycle, such that the lantern is supposed to light for 15 seconds upon a successful purification cycle.  I’ll be getting the newly designed replacement model within the next couple of weeks and will report on these changes in my Long Term Report.

A final note about cold temperature water treatment; the AquaStar has its problems with getting enough power at subfreezing, but that appears to be alleviated by using quality lithium batteries.  Chemical purification is ineffective or takes hours at temperatures below 40 F (5 C).  Filters are permanently damaged by microscopic ice crystals opening up the filter fibers.  Thus, it is nice to have the visual indication of the AquaStar UV tube lighting and end of cycle indicator that the water has been cleansed.

Test Locations and Conditions

Testing was conducted in east Oregon’s Eagle Cap Wilderness and areas around Idaho’s Saw Tooth Wilderness, thus elevations from 6000 to 9000 ft (1800 – 2800 m).  Temperatures dropped down to 14 F (-10 C) a couple of times at night and 65 F (18 C) during the days.  Water temperatures were 50 F (10 C) at the beginning of the test period and 38 F (3 C) just a week ago.  I could have found colder water in smaller creeks, but I tried to stick to warmer supplies.  There were a couple bodies of water that were somewhat stagnant at the beginning of the test period, and they made me a little nervous.  I have yet to get sick from the water, thus the unit is effective in eliminating the parasites or there were no little nasty’s in the water. 

Backcountry fall testing is coming to a close as winter sets in, but I still get out and day hike.  After Christmas, I’ll have a couple of overnight snow camping trips, and there will still be water in some of the larger creeks.  The water will be cold, but the manufacturer has stated that the unit will purify down to freezing, but needs to be cycled 2 or 3 times to kill 99% of the parasites.  After that, the unit will be testing in sunny Mexico.