Potable water tank cleaning

[jefflance512]

Bought a RV second hand from someone that had less of a clue than I do about a year ago. My 1st RV.
BLUF: How do I thoroughly clean the black chunks out of my potable water tank?
I've recently started looking at the potable water tank and noticed that it looked like it had some black scaling on the inside.
I filled the tank put a cup of bleach, let it sit for several days, drained it down to about half, road it around for 30 min or so drained it, several chunks of the black substance came out, still see a good bit on the walls , took a larger clear hose sprayed water on the inside, used it to drain larger chunks.
When you touch the chunks that come out the dissolve.

 

[Phillbo]

Might be time to call in a pro and have all the tanks cleaned. Start fresh. Don't forget about the water lines. They need to be sanitized as well... be sure to run your bleach through them.

 

[MNC]

I don't know for sure but it could be black mold. the former owners might have left some water in for a long time

 

[jefflance512]

Bought a RV second hand from someone that had less of a clue than I do about a year ago. My 1st RV.
BLUF: How do I thoroughly clean the black chunks out of my potable water tank?
I've recently started looking at the potable water tank and noticed that it looked like it had some black scaling on the inside.
I filled the tank put a cup of bleach, let it sit for several days, drained it down to about half, road it around for 30 min or so drained it, several chunks of the black substance came out, still see a good bit on the walls , took a larger clear hose sprayed water on the inside, used it to drain larger chunks.
When you touch the chunks that come out the dissolve.

I have decided to replace the tank, no need for any other replies.
I don't think I would feel safe drinking even if someone cleaned it.
And probably cheaper with a self install

 

[T’sOVR&Explore]

Just an opinion from two points of reference:
1. We don't ever drink from the rv taps. I even pour water in a cup from our drinking water jugs to wet my toothbrush and rinse my mouth afterwards. Did same for over twenty years, even though I never saw anything in the HR Alumalite's semi-see thru tank or at pump inlet, etc.
2. In my working career, got a firsthand view to concerns and mitigations related to potable water system used by astronauts on the ISS. Just because nothing is visible is not a guarantee a system is fit for use. Lots of attention was paid to the invisible, slick-to the touch surface condition found at times in tubes and storage vessels of that type of system.

A new tank is a nice refresh. Helps keep pump inlet screen clear and all that. But making use of carried water jugs for drinking, coffee and toothbrushing pretty much precludes the likelihood of sickness from bad water in the rv. Food for thought!

 

[Texas Clodhopper]

If you investigate how bottled water is bottled, you'll quickly learn that drinking from your tank isn't much different. The majority of bottled water is municipal tap water that may or may not have been filtered. The chemicals leaching from the plastic bottles are another issue.

 

[Rollin Ollen]

If you investigate how bottled water is bottled, you'll quickly learn that drinking from your tank isn't much different. The majority of bottled water is municipal tap water that may or may not have been filtered. The chemicals leaching from the plastic bottles are another issue.

We do a visible, smell and taste test before hooking up to any city water. Then I have a sediment filter, carbon filter and reverse osmosis filter and I'll bet my water tastes better and is safer to drink than most bottled water. Now going into Mexico we use a water test kit to.

 

[Texas Clodhopper]

@Rollin Ollen, I bet it is too.

 

[T’sOVR&Explore]

@Texas Clodhopper -
You are absolutely correct in all of that. Our protocol does expose us to the shortcomings of corporate bottling realities, but one circumstance in our past rv travels still stands out:

We pulled into and set up at a small town Kansas campground a day or two after massive rainfall there, in the mid 1990's with our then kids along, on one of our every other summer 37 day trips cross country. We later found out that the water treatment facility serving the taps was out of spec due the the foot of rain's influence. No taste or smell test was likely to inform us of low treatment levels in the water. No signs were posted or warning given about that when the teenager at rhe desk registered our arrival.

Same risk exists during boil water alerts ongoing whereever one may pull in to camp.. Not impacting us, back then nor now.

I chuckled at the mention of chemicals leaching out of the plastics. You are absolutely correct about that, too; The chuckle is that my other risky activities doing hot panel work as the fixer to call as the last resort, and touching 150 mph freqently during past commutes to work on a 2010 Yamaha Gen 2 Vmax motorcycle already had dibs on sending me early to judgement at the narrow gate.

The encountered exposed energized electrical equipment and the motorcyle in the garage are still unaware of the resident mercury amalgum of the 1960/1970's dental fillings in my teeth or Mama's steady use of her aluminum pressure cooker back then, which all got a big head start on slaying me years earlier.

Everyone has choices to make. I liked reading the other post about doing our own water testing, particularly for travel to Mexico. Seems like a solid idea..