What is this stuff in our water tank?

[mdd246]

We are wondering if anyone can help identify what has contaminated our new flexible water tank? We purchased it in January and installed it a few weeks ago. We had trouble with it from the start and determined that the tank contained something that was seriously clogging our water strainer. We could only run the water for approximately 10 minutes before the strainer became too clogged to operate. The attached photos show a sample from the clogged strainer.

We are unsure whether the contaminant is organic or non-organic. It looks organic but feels soft and porous like inorganic material. The tank has only been filled with treated water from town supply. We also use the boat's 2 original rigid water tanks which have never suffered any contamination. We have run separate tests on these two tanks and currently they contain no contamination.

We cleaned and flushed the flexible water tank and plumbing with a sodium hypochlorite solution which seems to have cleared the contamination. However we would like to identify the contaminant, as we had initially been using it for drinking water.

[GordMay]

Greetings and welcome aboard the CF, mdd.
Tapioca (cassava starch)?

[asistephen]

Take a sample to your Doctor and ask them to get it tested ASAP !

[jimbunyard]

I'm guessing it's almost certainly organic, but not so sure that it's biologic.

What effect does bleach or acid have on it?

[tkeithlu]

Nothing survives bleach, and you've used bleach. If there is no more of it in your water, but you're still concerned, continue to treat your water with just enough bleach to be detectable with your Mark I nose.

[S/V Illusion]

If you use the water from that tank for anything which results in contact or consumption, this isn’t an issue about which a guessing game should be played. And simply looking at it or the pictures is a guessing game.

Take it and a water sample to a lab which does cultures as well as chemistry.

[NYSail]

Looks pretty nasty whatever it is. Agree bring it and get tested. Did you call manufacturer of tank and ask them? Was tank thoroughly rinsed prior to instillation?

Good luck!
Greg

[SV Bacchus]

Originally Posted by tkeithlu

Nothing survives bleach, and you've used bleach. If there is no more of it in your water, but you're still concerned, continue to treat your water with just enough bleach to be detectable with your Mark I nose.

Yup, that is what we did in the Dominican Republic where even the locals won't drink the tap water!

[tkeithlu]

Hmm. Two issues here. First, how far to go in testing on this tank. I tend to be a hard-ass on checking out things like minor head injuries in an ER, but find myself more in the clean it out very thoroughly category here. Have you got a water-testing lab at hand? Municiplal water systems in the US use them, but I warn you, get an in-stream sample into a sterile container or you'll get back bacteria in every case. The second issue is keeping your tank water clean. We accept what our watermaker produces, and local city water, which is balanced to have a tiny amount of chlorine in it at the tap. We reject it only if it smells like the garden hose it comes out of. Maybe we should be adding bleach routinely, but in seven years we've never had our tank "go bad," we only dump it out if it has been sitting for months, and bleach does not improve the taste of gin and tonics.

Question, then. If a kitchen item like a pitcher grew stuff like you just got out of this tank, what would you do in cleaning it before accepting it back in your kitchen? Or, would you throw it away?

[tkeithlu]

Hey, Bacchus brother. Thanks for the Bleach/Water chart. A copy is going in my wheelhouse.

[Shrew]

I don't know that I could EVER trust that tank for potable water. Just because it no longer clogs a filter, doesn't mean the problem isn't still present.

[BBBest]

Looks like the stuff that chestnut trees give off (like tiny cotton balls with a small seed in the middle) in the spring, early summer. I realize that it would be odd to find it in the water tanks, but I live in a city with a lot of chestnut trees and I find that stuff in the strangest of places.

[a64pilot]

Originally Posted by tkeithlu

Nothing survives bleach, and you've used bleach. If there is no more of it in your water, but you're still concerned, continue to treat your water with just enough bleach to be detectable with your Mark I nose.

Yes, but a strong bleach solution is one way to test for organic,bleach usually bleaches out organics, but often has little to no effect on things that aren’t.
I’m sure this isn’t an exact science, but if you have “stuff” in your fuel, the bleach test is pretty good to tell you if it’s growing stuff, or just stuff.

Looks like “growing stuff” to me, some kind of algae or bacteria, slime, whatever. I’m no biologist though.

[Kim Gregory]

We found similar white particles even after rinsing the tank when new. I think it is talcum powder or similar stuff used when the plastic layers are assembled to prevent them from sticking together . Caused us no harm, just rinsed out the filter.

[Longinod]

I follow this forum in anticipation of joining the cruising community in the near future. For now, I'm stuck in my Aseptic processing Chem Eng. job. This "Stuff" is definitely organic, probably not bacteria as the water is not clouded. Probably a fungus or yeast of some sort. You did the right thing using bleach to clean the tank, I would repeat this on the tank at some frequency (3-6 months). As far as using municipal water, assuming they use chlorine, chlorine will dissipate from water over time, and if the water is held long enough the first inhabitants of our planet will succeed at proliferating. It's a problem, as soon as you make the water suitable/optimum for consumption, there's lots of competition for it. Cheers.
David