reactivating water tanks

[Bonzai]

Was wondering what you guys would use to freshen on board water tanks that haven't been used for around 10 yrs. The water has no foul odor and is running clear, but I would like to run something thru them that would sterilize/sanitize them enuff for tooth-brushing, dish-washing , etc. Appreciate all suggestions! They are plastic tanks circa 1999-2000.

 

[alexco38]

No tooth-brushing. We use bottled water.
dish-washing only but use bottled water to rinse after.


A few teaspoon of bleach to kill anything and a cup of vinegar to soak for a few days. Rinse many times to get rid of the vinegar smell.

 

[Stu Jackson]

Peggie Hall recommends:

Fresh Water System Recommissioning 101 http://c34.org/bbs/index.php/topic,5836.0.html

 

[Dan Hill]

I used Peggys method above on our 28.5 when we purchased it last year. The PO stated he never used the plumbing system in his 8+ years of ownership so I was worried like you. Worked like a charm and is part of my recommissioning from now on. Also works mid season when your system gets "eggy" smelling because you forgot to top the tank off

 

[Bonzai]

thanks guys!

 

[anchorclanker]

I was told to use that much bleach on our well once to kill that rotten egg smell, then flush it for an hour to clear the system. It took over a week to lose the bleach odor/taste. The lady at the health dept said a cap full or two should be enough. Cap, cup, makes a big difference when people mis-hear something and then repeat it.

I used to sanitize the water tank every spring in the motorhome. I would fill it with fresh, drain it, refill adding two cap fulls of bleach, and leave it sit overnight after running the sink taps (hot too) until I could smell bleach, then top it off full. The next day I would drain and fill twice and it was good to go.

The water should not only be potable, but the hose you use should be RV type potable water hose, not common garden hose.

 

[Steve Dion]

Something to consider! Peggie would tell you that bleach is NOT a cleaner so you may want to consider a multi-step process. Simple green makes some products that may help. If you disinfect the the tank and then clean it with their products your wanter should be fine for consumption.

We use our water tank for bathing, dish washing, coffee and other assorted things. We typically refill our tank every 2-3 weeks depending on the time of the year.

From the folks at Simple Green:

"Thank you for contacting Simple Green and for your interest in our products.

Crystal Simple Green, used in conjunction with Simple Green d Pro 5, would be the ideal choice for cleaning and disinfecting a water system on a boat. Begin by cleaning with Crystal Simple Green at a 1:30 dilution ratio, flushing through the lines then rinse well with clean water. After cleaning you can mix a 1:64 dilution ratio of Simple Green d Pro 5 and run that through the lines insuring that the product stays wet on surfaces for at least 10 minutes. After 10 minutes, flush the product through the lines with clean water. It is important to insure that all of the cleaning and disinfecting products are thoroughly flushed from the lines prior to filling the tank and running water again.

Crystal Simple Green and Simple Green d Pro 5 are both available at the Home Depot website (www.homedepot.com)."

 

[Steve Dion]

I don't think that a couple of cap fulls of bleach is going to do much to shock any holding tank.

I believe that you need a cup of bleach for every 25 gals. of water. They recommend that you drain the tank then fill it half way with fresh water. Mix you bleach solution with water and pour it in the tank. Then finish filling the tank with fresh water. Open all of the fixtures until you smell the odor of bleach.

Let it stand in the tank and lines from 8-24 hrs. Then drain the tanks and flush with fresh water until there is no longer any bleach odor.

 

[Jerry Clark H356 SV Persi]

I have used Peggy Hall's method for 11 seasons and we drink the water, brush our teeth, make coffee, shower just like we do at our home. We run through our water every two to three weeks (75gals).

I didn't go to the link Stu Jackson posted to make sure it fully describes her method, but assuming it does, it will work. You have to flush out your system with several changes to get the excess chlorine out after using this method or you can use cider vinegar to kill the chlorine and flush that out. If your system has a lot of algae in it, I would clean it well too! I haven't needed Steve Dion's method, but it looks good for cleaning, follow up with Peggy's method.

 

[RichH]

There is probably more misinformation on water system cleaning and sanitizing than correct or 'spec' cleaning procedures by 10:1.

1. If there is an apparent 'film' in the water system or tankage, thats a massive bacteria colony called a calcyx ... and it doesnt matter if its still 'wet' or dried out it has to be removed either by mechanical scrubbing or 'successive' soaks of sanitizing agents. Such a 'colony' is or was alive and will prevent the sanitizing agent from contacting the walls and inner surfaces of the water system.
How does one 'detect' a 'film' in a water system? You open up the system, and with yoiur fingers you 'wipe the walls or inner surfaces' ... anything that feels 'slimey' is considered a calcyx, a large massive bio-film of growing bacteria.

2. For a CLEAN (prior SCRUBBED OUT or NEW) system the standard municipal 'dosage' of 'chlorox' is 10-15 parts per million chlorine (about 40 ounces 'clorox' per 100 gallons of water) and with a minimum soak time of 1-2 hours. This is the standard recommended dosage by the National Sanitation Foundation - NSF for NEW or CLEAN systems.

2a. If the system has a 'bio-film' or 'calcyx', repeated dosing at the above 'strength' interspaced with 'high velocity flushing' until the bio-film is removed from the surfaces. Dont do that with a living bio-film and the bio-film will 'shield' the growing bacteria from the sanitizing agents, those agents only kill/stun the upper surface layers of the bio-film.

3. After cleaning/shock sanitizing. The standard municipal chlorine dosage is approximately 1 parts per million of chlorine .... or about 4 ounces of "Clorox" per 100 gallons of water ... or 0.4 ounces per 10 gallons capacity. What the 'maintenance' dosage does is prevent the remaining bacteria in the water from growing / multiplying.
The 'best' way to ensure that you have 'free' or active chlorine in the system, is to 'work up' to that 1 parts per million dosage by slowly adding 'just enough' clorox/chlorine so that your can with your NOSE discern the 'barest' possible aroma of chlorine from the spiggot discharge ... and chlorine will continually react with the structural components of the system; so, you need to 'monitor' occasionally for that 'barest smell'. If you simply do a cookbook dosage and then forget about it, eventually the chlorine/clorox will be 'consumed' .... and you will be growing another large 'calcyx' quite soon. What you dont want to do is to 'overdose' the system for 'maintenance' as chlorine is not a very good thing 'to drink', health-wise. If your dockside water is from a municipal supply you dont have to continually 'redose' it with clorox; if the supply is from well water you should consider an occasional sniff of the spiggot water.

How does bacteria constantly get into tank water? chief source is probably from the atmosphere .... every time you draw down the tank bacteria laden air is being pulled into the system through the 'tank vent'. Make SURE that your 'vent' is in a CLEAN place, not 'loaded' with 'growing CRUD' .... and simply when the vent is restored to 'clean', put/tape a large fist-sized 'wad' of 'bandage cotton' over the end of the vent and cover with bandage gauze ... keep the 'filter' dry, and change every year. Clean out your tank vent, replace if 'discolored' / stained.

Rx: Start with a clean, scrubbed out tank .... the only way to be sure that its not 'grossly contaminated'. If you cant open and inspect the tank, consider to shock sanitize SEVERAL times. Once properly 'sanitized', then do routine dose maintenance ... by using your nose - that 'barest possible aroma' of chlorine in the spiggot water.

Dont do the above, ... then expect an occasional bout with "the trots".

;-)

 

[Forrest15112]

I home brew beer and one of the most important things is sanitizing bottles, kegs, & fermenters. I use a one step sanitizer that is basically oxalic acid. It's cheap, requires very little added to water, sanitizes with 30 seconds contact, and doesn't require thorough rinsing. It's easy on your hands too. I always thought this would be a good alternative to bleach.
http://www.austinhomebrew.com/product_info.php?cPath=178_56_36&products_id=503

 

[Bonzai]

As usual some great input from everyone! My tanks have been empty for years, after filling one of the 4 tanks the water seemed fine with no greasy feel or bad smell. It also runs clear so I feel problems with it are minimal. I am wanting to make sure they are clean before using, even if all 4 tanks run clear and odorless, cause if the Admiral gets ill from it you know the fun stops..lol. Thanks for all the time and effort put into these responses! I will fill and check the other tanks next week when I return to Brunswick. Then will make good use of all this info! Thanks again for each response!

 

[RichH]

I home brew beer and one of the most important things is sanitizing bottles, kegs, & fermenters. I use a one step sanitizer that is basically oxalic acid. It's cheap, requires very little added to water, sanitizes with 30 seconds contact, and doesn't require thorough rinsing. It's easy on your hands too. I always thought this would be a good alternative to bleach.
http://www.austinhomebrew.com/product_info.php?cPath=178_56_36&products_id=503

Sodium meta-bisulphite.
Such is also used to sanitize and stabilize 'watermakers' for long term storage.
Sodium Meta-bisulphite (toxicity): http://www.livestrong.com/article/367978-sodium-bisulfite-toxicity/
Use only if you also have the proper 'dipstick' (test strips) to indicate complete removal by flushing/rinsing, otherwise you can 'pickle' your innards.

 

[Forrest15112]

Sodium meta-bisulphite.
Such is also used to sanitize and stabilize 'watermakers' for long term storage.
Sodium Meta-bisulphite (toxicity): http://www.livestrong.com/article/367978-sodium-bisulfite-toxicity/
Use only if you also have the proper 'dipstick' (test strips) to indicate complete removal by flushing/rinsing, otherwise you can 'pickle' your innards.

What I linked to is not Sodium Meta-bisulfate. It's a mixture of Sodium Percarbonate (oxyclean) and Sodium Sulfate.

 

[Gunni]

Rich, need to check your calculations, it takes less than 2.5 ounces of common bleach (5.25% NaClO) to bring 100 gallons of water to 10 mg/l of chlorine. And 1/4 ounce common bleach to produce 100 gals of water at 1 mg/l chlorine.

Center for Disease Control (CDC) guidelines (pdf link) recommend 1/8 teaspoon per gallon (2 ounces/100 gallons) common unscented bleach (5.25% NaClO) but that puts the total chlorine level to 8-9 mg/l (ppm), too strong to drink. Take the concentration to 10 mg/l (10 ppm) and you have a chemical shock sanitizer. Treat your tanks with this concentration, go boating for a few hours and flush it. Then refill with water treated to 1-2 mg/l chlorine.

I have found that common bleach (5.25% NaClO) does a fine job of making water safe for immediate drinking at low dosages. 2 mg/l (2ppm) is fine. That is 1/2 ounce per 100 gals. It will still have a chlorine smell to let you know it is there.

As you can see, it doesn't take much bleach to shock sanitize a tank, or make water safe, and drinkable.