Fresh water lines

[Tiemo]

In an effort to have clean, good tasting water I have scrubbed the freshwater tank with a bleach / water solution; added a Pentek Carbon Block filter at the cold water supply line (after the pump and accumulator and just before the galley sink and head supply). I also started using an inline filter at the hose when I fill the tank. The water flows and tastes great. However, I am looking for a method of treating the supply lines that does not involve using bleach as I have read bleach can be the kiss of the death for the water pump impeller. Any tried and true suggestions are appreciated. Replacement is an option but, there must be some safe way of treating the supply lines that does not involve knowingly cutting the life of the water pump short?

Thanks.

[a64pilot]

We have had our boat for five years, been living aboard full time for I guess two years now.
I have never put a drop of bleach in the water, and I filter all dock water going in with a carbon block filter to remove chlorine.
When we cruise which we do for six months at a time, we make water, which of course has zero chlorine and I have never added any.
Growing up we lived in a couple of different houses that had their own wells, and of course no bleach ever in well water.
House before my last one we had a well.
We have never had a problem, and I don’t understand why people want to constantly bleach their water. For a very long time people have lived in houses on well water and no bleach, so what’s with the bleach?

[Tiemo]

Thx for the reply. Suppose you are right. I used a shop vac to extract the light bleach solution used for scrubbing the tank from the tank so I didn't run that dirty water through the lines. I had good visibility into the tank before and after cleaning. There was a thin, opaque, oily type layer of smudge over the entire interior that is now gone. The boat was built in 91', I bought it in Nov 19' and am the 4th owner. I had to look, and then had to clean it for peace of mind.

[thinwater]

All of the rubber parts in any flush toilet are exposed to blach. The rick it to keep the bleach dose down to just a few ppm.

Also consider Cleantabs. Bleach, in a sense (sodium dichloroisocyanurate), but buffered in a way that much less is available to cause corrosion or damamge. I've used these for years. Very handy, no measuring (you will probably break tabs to match the tank size, and you can used ~ 1/2 the recomended amount, which is for dirty water).

[Lepke]

Eventually every water tank gets some organisms. If not in the water, it comes in the air thru the air vent. As the boat heats and cools air moves in and out of the tank.

If you take on city water, it probably has some chlorine. I make all my water, at my home dock or cruising. In 10 years with the current boat I added minimal bleach twice. I filter my water before the watermaker and at the galley sink and love my water taste.

[Chotu]

I've always (nearly 30 years now) run straight bleach through the water pump. No issues.

[billknny]

Unless you are taking on water that is suspected of harboring pathogens, bleach will always do more harm than good. If you actually have a biofilm that has attached to the wall of the tank, bleach will not reliably kill it anyway. You have to scrub it off.

Our boat has a significant amount of copper pipe. It lasts forever... unless hit by high levels of free chlorine. Several sister boats have had a copper raw water manifold fail. Never fails they took some bad advice and dropped a "solid bleach" tablet in the raw water strainer to keep things from growing in the raw water system.

Our toilet joker valves last YEARS (literally) because they never see any chlorine above that in city water supply (which is mostly chloramine in the USA these days in any event).

You will NEVER get your tank water sterile, no matter what you do. Don't try. Keep it clean and take on clean water, and you'll be fine. Don't use clear hose where light can get to it, so it doesn't grow algae.

The only time I would EVER add bleach to my tank was if I was forced to take on tap water in a place I would not drink the tap water. That's not going to happen unless I have a failed watermaker.

[Mike OReilly]

We cruise for about six months per year. We usually flush our water system at the start of each season, using the recommended shock-level of chlorine (bleach). I forget the concentration off hand, but it's something like 10x the normal municipal water level.

This sits for a few hours, then it gets flushed out through the system, including pumps and faucets. And then the whole system is flushed repeatedly a few more times.

In the nearly 10 years of owning this boat, and then another 10 with a previous one, I've never known this to cause any problems to tank, pumps, valves or hoses.

Municipal water usually contains chlorine, so most boat water systems have seen it. I've never added any bleach to water in use, but if I was suspect of the source, I might.

[Chotu]

I'll add I usually put some chlorine into my fresh water tank to keep it longer. 1-2 tablespoons per 50 gallons makes for water that stores very well. Fresh and nice for all purposes. Keeps the whole water system fresh too.

For drinking, I like 0% chlorine so it's run through a carbon filter at the drinking tap.

It's worked well forever, though this time, I'm going to have a water maker so the throughput of wasting all that water will probably keep the system more clean.

[Bean Counter]

Lived aboard for 5 years, bleached lines every six months. No water pump failure, ours used rubber diaphragm not an impeller though.

[thinwater]

A common reason for adding bleach has to do with off tastes. This is a regional problem, related to water chemistry, and many sailors have no experience with it. My marina runs on well water that goes quite skunky unless treated. It's OK out of the tap, but let it sit for a few weeks and oh boy. This is common around the Chesapeake Bay.

The water contains sulfate, which is harmless. In the absence of oxygen, and with the help of facultative bacterial, the sulfate is reduce to sulfide and hydrogen sulfide (rotten egg) is released. It takes only the tiniest amount to make the water funky, too little to actually smell. Humic acids and other trace organics, often from marina well water that has not been chlorinated, are also a source of odd tastes. Bugs that wonder in the vent (add a strainer to the vent--the land-based plumbing code requires it) and bio-film in the tank (wash and dry the tank at the end of each season) are other sources. Just a trace of chlorine will oxidize the sulfide back to sulfate and oxidize the organics, after which the excess chlorine expends itself by oxidizing the carbon block filter (that is how carbon removes chlorine--it is sacrificially oxidized). The result is fresh tasting water.

This isn't just paranoia about a few bugs. Chlorine can be used to eliminate off-tastes through chemistry. This is, in fact, a pert of the municipal water treatment process works.


If your water source is chlorinated municipal water and there is no off-taste, there is no good reason to chlorinate it. Many sailors have learned this. You chlorinate if the safety of the source is unknown or if there is a taste issue that chlorine can eliminate.

[bstreep]

Might also consider replacing lines with PEX. Took us a weekend to do our boat. 21 plumbing connections.