Water testing and filters

[craigprice]

I stupidly got myself a water tester for peace of mind about my water filters - figuring I could verify if still ok
I started with a simple kactoily tester. I’m not sure I understand all the metrics yet well enough to interpret results fully, but I am learning and think I might have been happier before I knew so much

Because some of the mountain streams I thought were good water score pretty poorly on several important metrics. I’ve been quite shocked at how poor is the water quality in many of our mountain streams.

I’d switched to Katadyn befree filters quite some time ago, using them to remove nasties like E. coli and Guardia (and highly successfully in my experience over the last 8years), and not worry so much about other things - as I thought the water was pretty good - but after seeing the results of tests on filtered water in some streams I’d previously considered good water, I’m now moving back to sawyers and grayls to substantially increase the filtering of chems and other things.

Has anyone else looked into this with portable water testers or have experience with same ?

[bernieq]

Because some of the mountain streams I thought were good water score pretty poorly on several important metrics.

So many questions arise !
What metrics are you testing & what values are you seeing? Are you testing both before and after filtering? Which mountain streams are we talking about? What are the contaminants that are causing you concern?

[JohnnoMcJohnno]

What were the metrics that you found which were of concern? I remember looking at cheap water testers many years ago, not for hiking but because I am on tank water at home, but none of the testers I looked at gave me much confidence. For example they didn't actually measure E Coli or Giardia, but relied on measuring carbon in the water. Fair enough I suppose but I couldn't see how the tester could tell the difference between a giardia bug and something harmless like a leaf or a piece of bark. In the end I decided the only thing I was really worried about was lead contamination, so I sent a sample away to a proper lab which came back with a zero result. Everything else in the tank I am relying on filters and UV sterilisation and haven't been sick yet.

Similarly I've never considered testing water when I hike. I'd probably be horrified if I knew what I was drinking. I usually use a befree or micropur tablets, and haven't had problems. I did watch a series of Gear Skeptic video's on Youtube where he checks out various filters and purifiers and from memory the Sawyer Squeeze came out on top, but I personally haven't felt the need to change over.

[crollsurf]

That's interesting. I thought the Befree and the Sawyer used the same filtering technology!

[JohnnoMcJohnno]

That's interesting. I thought the Befree and the Sawyer used the same filtering technology!

Just went and had a quick look at the gear skeptic video again - and you're right. The big difference is the Sawyer life span is longer, I think they use a thicker walled tube. Here are the relevant snapshots from the video.

[craigprice]

Well that’s interesting
I started with the kactoilly water tester : https://kactoily.com/products/kactoily- ... 7919642917

Metrics it tests via conductivity etc are :
COD (Oxygen Consumption),
TOC (Total Organic Carbon),
TDS (Total Dissolved Solids),
EC (Electrical Conductivity),
UV275 (Ultraviolet Absorption Value)

Results from last trip

Worst case - untreated -

After filtering with my brand new befree filter -

I will post new test results from the weekend on Sunday.

[bernieq]

Are you running the tests on several samples from the same batch? I'm wondering about the repeatability of the results.

The pre-filtered results look quite reasonable to me.

COD (dissolved oxygen) is irrelevant for drinking purposes. TOC (total organics) is a proxy for bacterial contamination (as Johnno has alluded) since bacteria need the organics to grow. Pre- and post- test values are quite similar. EC (electrical conductivity) is irrelevant, really, as it's primarily measuring dissolved salts and in surface water (ie rivers) 100 - 1000 us/cm is considered normal.

I'm interested to see what new results you get - and where from.

[craigprice]

Thanks Bernie
I didn’t get away this weekend, gardening wore me out - will have to look at this next week if the weather is fine
Agree with all your points.