water tanks, clean or replace

[jbloyd]

Bleach at $2 to $4 per gallon is a lot less expensive.

True, about 10x more per gallon. I was thinking mainly of it being less harmful to the tank material. Many of the comments mentioned that bleach is "bad" for Aluminum and SS water tanks. And, hospitals use hydrogen peroxide as as a germicide instead of bleach. Is this really just a non-issue as long as I don't intend to store bleach in the tanks? Or, why the warning about bleach and then the instructions to go ahead and use it? Did I miss the step about first replacing the existing tanks with GRP or spun PP? I don't mind paying more, if it's a benefit (besides not smelling bad or being bad for my internals).

 

[firehoser75]

I will not profess to be an expert on the chemical reactions involved.
However, water tanks are often very difficult to remove and replace and are not cheap! Therefore, if I can do ANYTHING to avoid that I will. I have aluminum water tanks and have it from what I consider to be pretty good authority (and I don't want to risk long term damage to my tank) that chlorine stored (residual in tap water) or used in higher concentrations is not good for aluminum tanks (SS as well). It can do long term damage.

Therefore, I filter my dock water before putting it into the tank to remove some of the residual chlorine. When disinfecting my tanks I use Thetford Freshwater Tank Sanitizer instead of bleach, even though it probably costs me about $20 per year more!!!! I bit more time as well, as it is a 2 step process.
To each his/her own and it is your money. But my tank is now almost 18 years old, and I want it to last at least another 18 . To remove it, would require cutting out the galley floor, so, not something I want to undertake.
I haven't looked, but I would guess that I cannot get a new 150 gallon tank for $400?? My free advice, why take the chance??

 

[LongStoryGB36]

If there is a leak in the line, that's the likely reason for pressure loss. The tanks are likely stainless so with a minimal cleaning they should be good for some time. There should be access ports on the top of them for getting inside to wipe them out.

We have a 1977 GB 36... tanks are aluminum which was pretty standard for the time period. You need to be careful with bleach and aluminum.

 

[bgillroy]

Suggest you inspect internal welds for rust corrosion. Although tanks SS in that era improper weld rod and or welding technique often caused weld deterioration from inside which in turn means rusty water as water agitates during travel. You'll be cleaning filters often.

 

[jclays]

Remove filters add 1/4 cup of bleach per 15 gallons of water. Let it go thru the whole fresh water system and let it sit for a few hours. Flush system with fresh water several times to remove bleach odor. Install new filters.