Cleaning fresh water tank on my SM2K


David Kurtz
 

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan


Thomas Peacock
 

We have a similar appearing tank. I also shocked it with chlorine, with little cosmetic improvement. 
My sense is that it is classic mildew. Even if you kill the fungus, the dark stains will persist unless vigorously scrubbed.
I drink it nevertheless. As my mother told me, everyone has to eat a pound of dirt in their life. 

Tom Peacock
SM 240 Aletes
Chesapeake Bay

with its tiny keyboard

On Nov 6, 2020, at 10:07 AM, David Kurtz via groups.io <Davidwkurtz@...> wrote:

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?
<214D1856-A9F4-4713-BDFD-CA75CE8E2004.jpeg>

--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan


--
Tom Peacock
SM 240 Aletes
Chesapeake Bay


James Cromie
 

Hi Dave.  I’m familiar with this view!  Last year, I opened up all of the ports, and found mold balls on the walls of the water tank.  I flushed our tanks with bleach solution as described elsewhere, but this will not remove the adherent growth.  You will need to mechanically clean the surfaces, which is a bit tedious.   I did this by using a soft putty knife attached to the end of a broomstick or similar.   I let everything sit in a bleach solution for 2 days, which likely helped to loosen a great deal of the residual material.  Once removing all of the adherent material with the scraper, I repeated the process with a scrub brush attached on an extension.   

I then sprayed water and used a portable pump with a long hose extension to suction out all of the particulate material.   This was repeated numerous times until all debris was evacuated.  Finally, I fully filled the tank again with a dilute bleach solution, let sit overnight, and then drained completely.   One lide of the tank was kept accessible so that I could easily use the portable pump to drain the water quickly.  (I used a high capacity Parmax puppy pump (50 gal / min) that I keep on board as an auxillary bilge pump if I needed to evacuate water from the cabin for any reason.  

For simplicity, I simply wire it onto my gray water bilge pump switch and used that as a temporary means of supplying the 24V power for the pump. 

Perhaps someone else out there has a better idea than what I felt I needed to do to clean the tanks  completely… 

James Cromie
SV Soteria
SM2K 347
Anacortes,WA


On Nov 6, 2020, at 07:07, David Kurtz via groups.io <Davidwkurtz@...> wrote:

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<214D1856-A9F4-4713-BDFD-CA75CE8E2004.jpeg>
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan



James Alton
 

David,

   We cleaned the tanks in our Maramu and they were much worse than your, in fact we even had live snails living in there!  There was also significant amount of sediment in the aft low end of the tank.  I just used the bleach version of Soft scrub and a medium deck type brush with an extension handle to clean our tank followed by lots of flushing and pumping.  I was concerned that the abrasive powder in the Soft Scrub might be abrasive so I used a portable diaphragm pump to remove the water and debris instead of the ships water system. Obviously rinse the tank from forward to aft to flush things downhill.    Maybe be a little careful with the putty knife in case you encounter some loose gel coat, some came loose on my boat just from the scrubbing.

Best,

James
SV Sueno
Maramu #220

On Nov 6, 2020, at 10:07 AM, David Kurtz via groups.io <Davidwkurtz@...> wrote:

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<214D1856-A9F4-4713-BDFD-CA75CE8E2004.jpeg>
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan



 

It is difficult to get you head around this but to set your expectations maybe you should try to see the inside of your local municipal water tank. Here is a real photo:
image.png

As for strange solutions, when we were at Bonaire in the Caribbean, we visited a house that was being built for some American cruising friends who had successfully immigrated to Bonaire.  Residents of Bonaire collect rainwater for their primary freshwater source. Freshwater can also be delivered by truck to the residents. Judy and I were amazed that the locals place a certain type of fish in the tanks to keep the "growth" to a minimum. I wish I could remember the name of the fish. 

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Nov 6, 2020 at 10:36 AM James Alton via groups.io <lokiyawl2=aol.com@groups.io> wrote:
David,

   We cleaned the tanks in our Maramu and they were much worse than your, in fact we even had live snails living in there!  There was also significant amount of sediment in the aft low end of the tank.  I just used the bleach version of Soft scrub and a medium deck type brush with an extension handle to clean our tank followed by lots of flushing and pumping.  I was concerned that the abrasive powder in the Soft Scrub might be abrasive so I used a portable diaphragm pump to remove the water and debris instead of the ships water system. Obviously rinse the tank from forward to aft to flush things downhill.    Maybe be a little careful with the putty knife in case you encounter some loose gel coat, some came loose on my boat just from the scrubbing.

Best,

James
SV Sueno
Maramu #220

On Nov 6, 2020, at 10:07 AM, David Kurtz via groups.io <Davidwkurtz@...> wrote:

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<214D1856-A9F4-4713-BDFD-CA75CE8E2004.jpeg>
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan



James Cromie
 

Great source of Iron!

On Nov 6, 2020, at 09:34, CW Bill Rouse <brouse@...> wrote:

It is difficult to get you head around this but to set your expectations maybe you should try to see the inside of your local municipal water tank. Here is a real photo:
<image.png>

As for strange solutions, when we were at Bonaire in the Caribbean, we visited a house that was being built for some American cruising friends who had successfully immigrated to Bonaire.  Residents of Bonaire collect rainwater for their primary freshwater source. Freshwater can also be delivered by truck to the residents. Judy and I were amazed that the locals place a certain type of fish in the tanks to keep the "growth" to a minimum. I wish I could remember the name of the fish. 

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Fri, Nov 6, 2020 at 10:36 AM James Alton via groups.io <lokiyawl2=aol.com@groups.io> wrote:
David,

   We cleaned the tanks in our Maramu and they were much worse than your, in fact we even had live snails living in there!  There was also significant amount of sediment in the aft low end of the tank.  I just used the bleach version of Soft scrub and a medium deck type brush with an extension handle to clean our tank followed by lots of flushing and pumping.  I was concerned that the abrasive powder in the Soft Scrub might be abrasive so I used a portable diaphragm pump to remove the water and debris instead of the ships water system. Obviously rinse the tank from forward to aft to flush things downhill.    Maybe be a little careful with the putty knife in case you encounter some loose gel coat, some came loose on my boat just from the scrubbing.

Best,

James
SV Sueno
Maramu #220

On Nov 6, 2020, at 10:07 AM, David Kurtz via groups.io <Davidwkurtz@...> wrote:

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<214D1856-A9F4-4713-BDFD-CA75CE8E2004.jpeg>
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan






Karen Smith
 

Your trivia for the day....

The fish added to cisterns is usually Gambusia affinis the "mosquito fish" a close relative of the "guppy," and very similar looking.  

I don't know about on Bonaire, but on some of the other Caribbean Islands if you have a cistern you are required to keep a living population of Gambusia, or treat regularly with a chemical larvicide to keep mosquito larvae in check. People chose one or the other depending on their own personal bias against fish poop, or chemicals!


David Kurtz
 

Thanks, everyone.  I’m going to follow along the lines of what James and James both did.  Scrub it down, hit it with another dose of chlorine bleach in the spring, close it up and not think about it for a year.  If anyone asks, I’ll just refer to it as my guppy fish tank...😊.  And Bill, you’re absolutely right.  We frequently installed level sensors, high water alarms, etc. in municipal water system tanks up here in southeastern Michigan and they are pretty crusty in there.  Consntruction crews will still, very occasionally, dig up wooden water pipes still in use.
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan


Gary Wells
 

I am going to stick my neck out a bit and say that first, it's not that bad, second a serious and time consuming effort may get only moderate results and finally, if you have a year of patience you'll see improvements by staying with a 'program' of treatments.

I've had good luck with using moderately strong concentrations of bleach (about 6 ounces in a tank fill-up) every third or fourth time I add water.

Having said that, living aboard we go through 1,000 liters pretty quickly when dockside.

After each "shock" the water smells strongly of chlorine for a day or two.  That's when it's time to wash the sheets :)

The next fill-up is plain water, and may still smell of chlorine very slightly depending on how far down we depleted the tank.  
Only on the third fill will I then flush the watermaker.  After that I'll add 1/4 tsp of the StarBright water purifier. 
Then the next one is plain water, then the next one (or one more if I lose count) is back to bleach.  It works out to about monthly to bi-monthly. 

The bleach treatments will kill a charcoal water filter quickly so I just use paper/fiber ones.  

I also believe that if we were to highly chlorinated water sit in the lines it would be detrimental to pumps and valves and especially the copper fittings (nipples) on the holding tanks, so we always make sure we use the "bleached tank" of water fairly quickly.

Give it two years and see :) 

Gary W.
SM 209, Adagio
Maryland, USA


RIck Stanley
 

What we did on our SM2K - after we got access to all the hatches - was to first shock the tanks with bleach, then hit them all with a pressure sprayer. Worked like a champ, considering our boat was left up on the hard for 5+ years, and the tanks were black inside.


Philippe BELLOIR
 

Sorry it’s in french, the file give all the recommendations for cleaning and disinfecting containers and pipes

Fair winds,

Philippe

 

De : main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] De la part de David Kurtz via groups.io
Envoyé : vendredi 6 novembre 2020 16:07
À : main@AmelYachtOwners.groups.io
Objet : [AmelYachtOwners] Cleaning fresh water tank on my SM2K

 

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan


James Alton
 

Dave and All,

   I wanted to add a caution and mention that Chlorine can apparently cause corrosion issues with stainless.  Since our stainless keel bolts, nuts and washers are located in the bottom of our water tanks, I am pretty leery about putting a bleach solution, especially a strong one in my water tank.  The soft scrub that I used did contain bleach but was rinsed away as the tank was cleaned to reduce the exposure.  If anyone with a more expert knowledge of the corrosion risks from using Chlorine in our tanks could comment, that would be helpful I think.

James
SV Sueno
Maramu #220

On Nov 9, 2020, at 7:46 AM, Philippe Belloir <pbelloir@...> wrote:

Sorry it’s in french, the file give all the recommendations for cleaning and disinfecting containers and pipes
Fair winds,
Philippe
 
De : main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] De la part de David Kurtz via groups.io
Envoyé : vendredi 6 novembre 2020 16:07
À : main@AmelYachtOwners.groups.io
Objet : [AmelYachtOwners] Cleaning fresh water tank on my SM2K
 
Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<image001.jpg>
-- 
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan

<Reservoirs_et_canalisations_d_eau.pdf>


Matt & Michelle Day, SM#208 SV Talia
 

Clorine can damage stainless with long duration exposure.  The duration depends on penetration of the passivation layer of the SS.  Once the passivation layer is oxidized, the clorine will pit the SS and increase the risk of stress corrosion cracking.

At the concentration and duration that the group is discussing...we are talking about years to have a detrimental effect.  If one is concerned, you can always re-passivate with citric acid and restart the clock. 

Just my two cents. 


Philippe BELLOIR
 

I confirm, chlorine is not friendly with inox, specifically with 304 type.

Some recommendations (temp, time and kind of inox) from dairy industry

 

De : main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] De la part de James Alton via groups.io
Envoyé : lundi 9 novembre 2020 14:21
À : main@AmelYachtOwners.groups.io
Objet : Re: [AmelYachtOwners] Cleaning fresh water tank on my SM2K

 

Dave and All,

 

   I wanted to add a caution and mention that Chlorine can apparently cause corrosion issues with stainless.  Since our stainless keel bolts, nuts and washers are located in the bottom of our water tanks, I am pretty leery about putting a bleach solution, especially a strong one in my water tank.  The soft scrub that I used did contain bleach but was rinsed away as the tank was cleaned to reduce the exposure.  If anyone with a more expert knowledge of the corrosion risks from using Chlorine in our tanks could comment, that would be helpful I think.

 

James

SV Sueno

Maramu #220

 

On Nov 9, 2020, at 7:46 AM, Philippe Belloir <pbelloir@...> wrote:

 

Sorry it’s in french, the file give all the recommendations for cleaning and disinfecting containers and pipes

Fair winds,

Philippe

 

De : main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] De la part de David Kurtz via groups.io
Envoyé : vendredi 6 novembre 2020 16:07
À : main@AmelYachtOwners.groups.io
Objet : [AmelYachtOwners] Cleaning fresh water tank on my SM2K

 

Good morning all!  I tried cleaning my fresh water tank using Bill’s alternate method (fill with bleach solution, let sit for 48 hours, drain, flush, etc.) and did not get the desired results.  The attached photo shows what I am dealing with.  Seems to be a couple varieties of mold that was not killed off by the bleach solution.  Now that I am opening up all three access ports I want to clean it with something that works, but doesn’t poison my whole family 😳.  What have some of you used for cleaning?<image001.jpg>
-- 
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan

<Reservoirs_et_canalisations_d_eau.pdf>

 


David Kurtz
 

Thanks, folks!  REALLY liked hearing about what chlorine might do to the stainless steel keelboats as I left a pretty strong bleach solution in the tank yesterday!  Have to get back to the boat tomorrow and rinse it all off.  Regardless, it may not look perfect, but it will be clean, which is kind of the goal.
--
Dave Kurtz
SM2 #380
S/V Celtic Cross

Detroit, Michigan


Slavko Despotovic
 

Hi,

I hove done some research on net and there are some sailors that use white vinegar for tank cleaning. It is more environmentally  friendly. Anyone have used this method for water tank cleaning? 
here is a link with explanation https://rvblogger.com/blog/safe-sanitize-rv-water-tank-vinegar/
I use white vinegar for my coffee machine cleaning and it is very successful. It is interesting that machine heats up the mixture of water in vinegar before it goes trough the machine. 
My water tank needs to be cleaned so I am looking for the best and friendly procedure.


Slavko
SM 2000
#279 Bonne Anse in Portoroz


eric freedman
 

I had cleaned my tank using a method outlined by Peggy Hall “The head lady” in her book.  She at one time owned Raritan.

She suggests using a strong solution of Clorox, then rinsing the tank with water. She then says add white vinegar to the tank and then rinse,

 

When I ran the water after an hour with the vinegar in the tank the water came out blue. I don’t think vinegar agrees with the copper on some

of the plumbing. I immediately pumped the tank and rinsed with fresh water.

Fair Winds

Eric

Amel Super Maramu #376

 

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Slavko Despotovic
Sent: Monday, December 07, 2020 5:31 AM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Cleaning fresh water tank on my SM2K

 

Hi,

I hove done some research on net and there are some sailors that use white vinegar for tank cleaning. It is more environmentally  friendly. Anyone have used this method for water tank cleaning? 
here is a link with explanation https://rvblogger.com/blog/safe-sanitize-rv-water-tank-vinegar/
I use white vinegar for my coffee machine cleaning and it is very successful. It is interesting that machine heats up the mixture of water in vinegar before it goes trough the machine. 
My water tank needs to be cleaned so I am looking for the best and friendly procedure.


Slavko
SM 2000
#279 Bonne Anse in Portoroz


karkauai
 

I had the same black growth in my tank the first time I looked.  I tried weak bleach solution, vinegar, power washer, all with inadequate results.  Someone suggested that the growth is probably a bacteria of some kind, as algae requires sunlight.  I don't know if that's true, but I finally got rid of it with a very strong bleach solution of 6 gallons in a tank full to the brim. I let it sit overnight and voila, all growth dead and debris lying in bottom of tank. I pumped it out with a sump pump, got the last bit out with my shop vac, then filled about 1/4 full before pumping through the fresh water system.  Two more rinses with dock water, then filled with dock water run through two charcoal filters, and flushed all the fresh water lines with that dechlorinated water.
I shock the tank once a year with 3 gallons of bleach, let sit overnight, and rinse/refill as above. The tank has stayed mostly free of growth on less it sits half empty for a few months. I try to leave the tank pretty full most if the time, and avoid using dock water if I can.
I also run the tank water through a charcoal filter before it is distributed to the faucets, shower, and the watermaker.
A small amount of brown stain remains in a few places on the sides of the tank, nothing I've tried gets it out.
--
Kent & Iris
KRISTY
SM243