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Reviewer Information
Gender:	Male
Height:	5' 6" (1.6 meters)
Weight:	159 lb (72.1 kg)
Email:	mike-at-pahiker-dot-com
Home:	Southwest Pennsylvania, USA
Background:	I’ve been hiking since ’65 with occasional backpacking trips (backpacking became a love affair in the early 80’s). My first sleeping bag weighed in at 8 lb (3.6 kg) by itself! These days my loaded pack only weighs about 15 lb (6.8 kg) sans food. While most of my adventures are in the Northeast I’ve also been spending a good deal of time in the desert Southwest and most places in-between. My trips tend be in the cooler months - September through May - as I’m not much of a hot-weather person.

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Initial Report - Oct. 23, 2020

The Clear₂O Personal Water Filter is a drinking-straw type filter where you place one end in the water then sip through the other end to drink filtered water directly from the source. You can also use it to fill up a container to drink away from the source. This is a two-stage filter consisting of a 0.1 micron filter media and an activated charcoal filter to improve taste. Either stage can be used independently of the other, and each can be replaced when their respective medias become clogged or expire.

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Product Information
Manufacturer:	Clear2O 2O.com">https://www.Clear2O.com	2O Package.jpg" height=300 style="clear:both; border: 3px solid green; border-radius: 3px;">
Size:	Stage 1: 5-5/8 x 4-7/8 (cir) in (14.3 x 12.4 cm) Stage 2: 3-3/8 x 4-7/8 (cir) in (8.6 x 12.4 cm) Assembled: 8 x 4-7/8 (cir) in (20.3 x 12.4 cm)
Weight:	Stage 1: 2.43 oz (69 g) Stage 2: 1.55 oz (44 g) Assembled: 3.95 oz (112 g)
MSRP:	$36.99 (US) Stage 1 Replacement: Not listed Stage 2 Replacement: $16.99 (US) for 2 units

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Initial Impressions

Safe water while hiking is essential, and water sources should never be trusted. Even if hikers adhere to the 200-ft (61 m) guideline on relieving away from water sources it’s hard to get animals to commit to it, so Giardia and Cryptosporidium are always possible, and not a happy ending to an outing. Infected animal waste getting into the water supply, then ingested by drinking unfiltered water, is the primary way it is contracted by people. The Clear₂O Personal Hydration Filter looks like a good way to easily and quickly treat water while hiking.

Package Contents

The Clear₂O filter comes in a blister pack containing the following items:

• Stage 1 Filter - this is the 0.1 micron filter
• Stage 2 Filter - the activated charcoal filter
• A 1L (1 qt) water bottle
• The instruction booklet
• A product brochure

The instructions seem fairly clear. The first instructions say to assemble the Stage 1 and 2 filters, fill a 1L (1 qt) water bottle, attach it to the inlet and squeeze the water through. Some dark water may come through at first, this is just the loose carbon in the Stage 2 filter. After this initial priming I am just to put the inlet side into the water and sip through the other end. It can be used with or without the Stage 2 (carbon) filter.

To use it to fill up a water bottle I am supposed to fill up a water bottle with water from the source (dirty bottle) then attach the bottle to the inlet side. Next attach the bottle I am going to drink from (clean bottle) to the outlet side. Now squeeze the dirty bottle to force the water through the filter into the clean bottle. If the clean bottle’s threads don’t match with the filter then a tube can be connected to the outlet nipple and the other end inserted into the clean bottle.

Every so often (after 10L/11 qt, or when the filtering is slow) the Stage 1 filter needs to be cleaned. To do this I am to remove the Stage 2 filter, fill up a bottle with 1 oz (28 ml) of clean water, attach it to the outflow side of the Stage 1 filter, then force the water through.

If it is to be unused for and extended time they recommend sterilizing the filter. To do this remove the Stage 2 filter, mix 1L (1 qt) clean water with 1/2 tsp (25ml) perfume and dye free bleach, attach the bottle to the inlet side of the Stage 1 filter, then squeeze the water through. Let it set for 30 minutes then run 1L (1 qt) clean water through the filter.

Whenever the filter is not in use the caps should be on so nothing gets inside.

Now, all that seems simple enough, but when I went to the Clear₂O website it shows the Stage 2 filter in the water (photo on left), but the direction flow indicators on the filter I receive indicate that the Stage 1 filter should be in the water (photo on right). I asked for clarification on this, and was informed that the image on the website is incorrect.

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First Use

I always test something before I take it out into the field so I have some idea of just how it works. In this case the Clear₂O was taken to a local park, unfortunately water levels were really low (currently in a moderate drought status) so the Clear₂O had to be held up to keep it from sucking up the mud and sand from the bottom of the creek. Also, even given the drought status in Pennsylvania, laying down to drink would get me wetter than the creek bottom. So I attached a hydration tube to the nipple on the Stage 2 filter, then drank through the hydration tube. This worked out well, and I was able to draw a clean, if meager, amount of water.

Drinking was pretty easy. With a new filter and pretty clean water drinking was only a little harder than drinking root beer through a straw. I was pleased as I thought that drinking through two filters was going to be more difficult than it was.

All was not perfect, however. Having the filter in such shallow water did allow some mud/sand from the creek to get into the filter. I tried doing the backwash after I got home, but there wasn’t much noticeable difference in how the filter looked (see before and after photos).

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Field Report - January. 23, 2021

Date	Location	Trail	Distance Hiked	Altitude	Weather
Nov 23, 2020	Patagonia Lake, Arizona	Blackhawk to Sonoita Creek Loop	4.6 mi (7.4 km)	3,655 - 4,217 ft (1,145-1,285 m)	Sunny; 72-85F (22-29C); 40% Relative Humidity
Observations:	Hot and dry, but nice views of the creek and lake. Stopped along the way for a drink out of the creek. Just dropped the Clear2O into the creek and sipped. Once we realized the cap was still on (ahem) and removed it drinking was pretty easy. I attached a hydration tube with a bite valve (just happened to be on the tube) so that we didn’t have to lay on the ground to drink. We found this to be much easier as it wasn’t even necessary to hold onto the Clear2O to enjoy a refreshing drink.
Dec 18, 2020	Sabino Canyon, Arizona	Sabino to Phoneline Loop	49.0 m (14.5 km)	2,680-4,285 ft (817-1,306 m)	Sunny; 44-80F (7-27C)
Observations:	This was an enjoyable hike on the back side of of the mountain. I took a side trail to hike up to the top of Seven Falls. Not a great deal of water flowing, but enough to stop for a drink and replenish my 17 oz (0.5L) pouch (thanks Clear2O for the bottle). This time I used it without the carbon filter. Drinking was a bit easier, and the water didn’t taste like anything but water. Drinking is easy, and I’m getting used to just dropping the purifier into the water and sipping. Filling up a bottle, however, is a bit of a task. Preparing for this I had to plan on carrying a “dirty water” container along with the water pouch. Worked like this: Put the dirty pouch into the pond and fill it up. Attach the pouch to the Clear2O filter. Upend the setup so the dirty pouch is upside-down and the water flows down into the drinking pouch. Squeeze the dirty pouch to get the water to flow through (even without the carbon filter it does not flow with gravity). First time, the process took about 10 minutes to purify the water. I’m sure I can cut a couple minutes off the time now that I know the process. I was solo on this trip, so I had no way of taking photos, sorry about that."
Dec 30, 2020	Bear Run Nature Reserve, Pennsylvania	Blue Loop	6.0 mi (9.6 km)	1,448-2,196 ft (441-669 m)	Cloudy; 28-30F (-2 - -1C)
Observations:	Cold, dismal day. This did bring up one issue I haven’t considered - water freezing in the filter. To prevent this I kept in the inside pocket of my fleece mid-layer jacket. Drinking in the winter is no different, and took no additional effort. This made me really glad that I added the hydration tube so I don’t have to lie in the snow to drink!

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Long Term Report - Feb 23, 2021

Date	Location	Trail	Distance Hiked	Altitude	Weather
Jan 16, 2021	McConnell’s Mill State Park	Loop made of several trails in the park.	10.4 mi (16.4 km)	1050 ft (320 m)	Cloudy; 20-26 F (-7-3 C)
Observations:	Cold day, cold water, even colder with windchills. Stream had some icy spots but was still running free. To keep the filter from freezing I kept it in the inner pocket of my fleece layer, not sure what would happen if the water froze in the filter, but I can’t imaging it being good. What I decided to test this time was filling a wide mouth water bottle - I came up with an idea that worked well. I used an old plastic 0.5 L water bottle (kind you purchase at a market), these are very thin and compress easily (I’ve done it just opening the bottle), filled it from the stream, threaded the inlet side of the filter onto the water bottle, put the outlet side of the filter into the mouth of my bottle, then squeezed the plastic bottle. I was able to get almost all of the water through the filter in under 2 minutes. Then repeated the process once more to fill my 1 L water bottle. Worked nicely, the plastic bottles weigh almost nothing, and are cheap to replace if they puncture. I didn’t have a camera with me on the hike, but I took a photo at home to show the setup.
Feb 11, 2021	Mt Lemmon, Arizona	Bridal Veil Falls	10.2 mi (	2111 ft (643 m)	Sunny; 42-64 F (5.5-17.8 C)
Observations:	An interesting hike, for Arizona. Things started out fine, a nice 58 F (14.4 C) brisk morning. Hike went well until we hit 5 miles, then we could see snow further up the trail (42 F, 5.5 C at that point), something we weren’t prepared for. We filled up out water bottles using the plastic bottle method I mentioned above, then headed back down. This plastic bottle method is working out much better than I had hoped for, and I plan on continuing to use this method. I’ve marked “Dirty Water”on the outside of the bottle so that I don’t confuse it with other bottles I have, though I could just toss it and replace it the next time I drink a sealed bottle of water.

Summary

The Clear₂O Having used the Clear₂O Personal Water Filter for three months now I’m liking it for a full-time filter. I can drink straight from a stream (preserving the water in my bottle/pack for later use), replenish my bottle/pack for longer hikes, or even do both without much of a change to the setup. Where I live (in the Northeast) water is plentiful, so carrying the Clear₂O is a lot easier than carrying a heavy hydration pack. I can stop anywhere along the way for a quick drink then keep going. In the Southwest, where water isn’t as easy to find I can drink straight from the stream, the fill up to finish the hike. Yeah, the Clear₂O is clearly (pun) a keeper!

Things I like:

• Easy to drink through when the filter is new, not much different than a soft drink through a straw.
• Taste is pretty close to bottled water, allowing for the difference in water sources.
• Don’t have to carry a heavy hydration pack, so long as I know water can be easily found.
• Easy to squeeze water through using an old plastic water bottle.

Things I don't like:

• Backwashing did not remove all of the residue just from sipping. Makes me wonder what will happen when I take some serious drinks.
• Instructions are confusing. They do not say if the Stage 1 or Stage 2 filter should be immersed. To add to the confusion the website shows the blue end being submerged while the flow arrows on the filter indicate the green end should be submerged.
• Not sure about the effect on the filter if water freezes inside, wish there were comments in the instructions about this.

Acknowledgement

This ends my Long Term Report, I’d like to thank Clear₂O and BackpackGearTest.org for the opportunity to test the Clear₂O Personal Water Filter.