Capn Chuck
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Wondering how many if any of you have aluminum water tanks. We need to replace a tank and the yard wants to build it out of aluminum. Any issues? Chuck
Aluminum water tanks.
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The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
RickB
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Some people say that aluminum causes ... what's the name of that disease where you forget stuff?
RickB
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Why not? They are no different than aluminum hulls with the water inside instead of outside.
Giggitoni
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I have aluminum tanks. I sent a grab sample to a local environmental testing laboratory a couple of years ago. I had them test for the presence or absence of bacteria (drinking water) and metals. The concentration of bacteria was fine along with the metals except for...aluminum. The concentration of aluminum was above the National Drinking Water Standards. So I have decided not to use the water for drinking. We load up with bottled water for drinking, coffee, tea, adult beverages and use the tank water for everything else: showers, washing dishes, etc.
RT Firefly
Enigma
Greetings,
C.R.A.F.T. disease. (Can't remember a freakin' thing.) Ususally contracted by long term married types. Regardless, if you have the choice, as mentioned above either non-aluminum or don't drink aluminized water. Now where did I put that Pong game?
C.R.A.F.T. disease. (Can't remember a freakin' thing.) Ususally contracted by long term married types. Regardless, if you have the choice, as mentioned above either non-aluminum or don't drink aluminized water. Now where did I put that Pong game?
OP
OP
Capn Chuck
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I appreciate all of the comments but I would really like to hear from folks that actually have aluminum tanks. Chuck
Phil Fill
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I told you I don’t remembered?
Something to do with the low galvanic rating of aluminum as compared to other metals? In some industry aluminum as a sacrificial metal. The reason they like aluminum is because its easy to weld and light weight to install. If you do ask them about installing, protection/preventive, galvanic, and absorbing in the water.
I don’t know of anybody that has aluminum tanks for water. There are better choices.
We had SS tanks with Al inspection ports/lids on our last boat. We would get a residue on the Al, heavy enough to fall into the tanks. I could clean the ports and within weeks, the residue would be back. We are looking at adding SeaBuilt inspection ports on our current tanks. They sell SS and Al systems and recommend SS for water.
Alfton
Boat Bum
My Pilgrim 40 came with 3 aluminum water tanks. I removed one to add to my storage space. The 1985 aluminum tank had what appeared to have a lot of white scale I am not sure what the scale was but I do not use the water in my water tanks for drinking or cooking.
RT Firefly
Enigma
Greetings,
ONE opinion: Aluminium and Alzheimer's disease - Alzheimer's Society
ONE opinion: Aluminium and Alzheimer's disease - Alzheimer's Society
I think you'll find that aluminum is considered a very poor choice for fresh water tanks because of the reasons previous posters have listed. Plastic tanks are great for all reasons except taste-- some can put a plastic taste in the water that never goes away, even with time. Other types of plastic apparently don't do this.
The tanks in our boat are original to the boat so are now 40-plus years old. They are stainless steel. The thing to consider in metal tanks, at least older ones, is lead in the welds. Our tanks probably have this but we don't worry about it. We use the water in our tanks for everything including drinking. But we use the boat year round so the water turnover is fairly high.
sunchaser
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My water tanks too are stainless, as specified by the designer very early on in his boat design career - Art DeFever. I lost a Seaward water heater made of Al, due to severe corrosion, after 9 years of use. The Al hot water tank gave off the white crud mentioned earlier by Alfton.
Not all Al is created equal. Some alloys are better than others for liquids. What does your tank guy say about Al alloy specs? IF you are planning on keeping your vessel for less than say 6-8 years Al may not be a bad decision but he next buyer may be wary. Many boats have Al fuel and water tanks, especially Al boats! If you go Al insure "perfect" install with no non Al in contact and no trapped water underneath.
Not all Al is created equal. Some alloys are better than others for liquids. What does your tank guy say about Al alloy specs? IF you are planning on keeping your vessel for less than say 6-8 years Al may not be a bad decision but he next buyer may be wary. Many boats have Al fuel and water tanks, especially Al boats! If you go Al insure "perfect" install with no non Al in contact and no trapped water underneath.
Phil Fill
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Because of aluminum’s low galvanic rating, zinc is 3, aluminum is 7 to 10, mild steel is 15 to 17, SS is 23 to 26, bronze/copper 27 to 30, and gold/silver 33 to 35. In some industries aluminum is used as a sacrificial metal. So if you do get aluminum tanks make sure you ask about the installation, protection/safe guards, and oxidation.
The best metal is still SS for water but it has to be left natural.
The best metal is still SS for water but it has to be left natural.
Chuck Gould
Senior Member
Quote from Tony Fleming: "Water tanks in Flemings are very heavily walled polyethylene, molded in one piece, and consequently they have no joints or welds. We previously used stainless steel, which (despite its popular reputation for excellence) in in fact vulnerable to crevice corrosion. The corrosion-resistant surface to stainless steel is only a few microns thick, and should this become disturbed and there be insufficient oxygen to replace it, corrosion can occur very rapidly. Especially at the welds. In some instances, we found that chlorinated water was sufficient to trigger the problem. Polyethylene is totally inert and is used universally for the storage of drinking water- as well as for corrosive chemicals."
Chuck Gould
Senior Member
Since I'm a big Fleming fan and have met Tony Fleming, I would love to know where this quote, attributed to Tony, came from.
From an extensive interview with Tony Fleming regarding the design and construction principles of his yachts.
You can download a pdf of the entire document here:
Luxury Yacht, Yachts for Sale, Brokerage, Fleming Yacht, Corvette Yachts - Chuck Hovey Yachts
sunchaser
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I notice on the GB Forum some problems with Al water tanks. One interesting post discussed a copper bonding strap contacting the full length of the tank. Out came the Al tank and in went a SS tank.
Regarding crevice corrosion in stainless water tanks I have wondered why the tanks in our boat have not yet succumbed to this as they are as old as the boat (1973). The only thing I can think of is that the water turnover int the tanks has always been fairly high. We go through a lot of water on our boat as we use it all year even when we don't take it out and perhaps the previous owners did the same.
I would agree that the tank construction described by Tony Fleming is superior as long as the tank material does not impart a taste into the water.
I would agree that the tank construction described by Tony Fleming is superior as long as the tank material does not impart a taste into the water.
Chuck Gould
Senior Member
You're probably not adding any chlorine to your tanks filled with Bellingham city water, either. (But there may be a small amount in the city water supply?) Tony seems to feel that the presence of chlorine is a contributing or accelerating factor.
JAT
Guru
A number of years ago...I replaced a cracked poly tank with an aluminum tank for water.... Only after the fellow finished and I paid for the tank... I was told I could have had a stainless steel tank for about $50 more!!
Maybe I occasionally suffer from CRS because the tank was aluminum, but I doubt it.... At any rate...i spent more than $50 more to prep the tank to install it in the boat....
Given my druthers.... I would go with a poly or stainless steel tank.
Or...custom build one with FRP...
You're correct--- we don't add anything to the water in the fresh water tanks. And I have no idea how Bellingham treats its water but when I've drunk from drinking fountains and such up there, there does not seem to be any noticeable chlorine taste.
HopCar
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If you decide to use a plastic tank, and I think you should, these are the guys you should buy it from: http://www.ronco-plastics.com/newRonco/index.php
They make heavy walled roto molded tanks in about 500 different sizes and shapes.
My Ronco water and holding tank are all over 20 years old now and I'm very happy with them.
They make heavy walled roto molded tanks in about 500 different sizes and shapes.
My Ronco water and holding tank are all over 20 years old now and I'm very happy with them.
Tidahapah
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I must agree with everybody else.
SS is the only way to go for small boat water tanks.
I had 2 x 1000 lt ss tanks in Tidahapah and after 15 years cut them open to decrease their size( I was fitting a water maker) in all this time there was barely any sludge in the tank bottoms , a quick wipe out new ends formed and welded in. Good as new. That was 4 years ago. Water is always perfect and I just run a carbon filter on the line to the galley sink.
No bottled water on this vessel as it is one of the great cons performed on the world wide public.
Cheers
Benn
SS is the only way to go for small boat water tanks.
I had 2 x 1000 lt ss tanks in Tidahapah and after 15 years cut them open to decrease their size( I was fitting a water maker) in all this time there was barely any sludge in the tank bottoms , a quick wipe out new ends formed and welded in. Good as new. That was 4 years ago. Water is always perfect and I just run a carbon filter on the line to the galley sink.
No bottled water on this vessel as it is one of the great cons performed on the world wide public.
Cheers
Benn
"Everybody else" did not recommend stainless steel tanks. Many recommended polyethylene. They are less expensive than SS, weigh less, and you can see the water level through the tank walls and/or install an external level sensor system.
Well I'll be fitting a 500ltr ally fuel tank in the aft and a 500ltr fresh water tank in the bow of my boat and will be installing it as per the methods in the bottom link.
The tank walls are 10mm thick and i have every confidence that they will work just fine without the risk of Crevice Corrosion. I'm not to concerned as to the so called "medical" disadvantages of aluminium tanks either
A correctly mounted aluminum marine fuel tank of high quality material, and under ideal conditions should outlast the boat. Some say they last 25-30 years, but I think they may go even longer as I've seen them past that mark and still in good shape. I've also seen some in the 15 year range that looked to be 50 years old due to crevice corrosion. Aluminium marine fuel tanks often have baffles in them to stabilise the fuel from swashing around excessively. Aluminum tanks are custom made, so getting one to match your boats design is a snap. A custom marine aluminium fuel tank can take advantage of extra space and allow for more fuel capacity. Aluminum fuel tanks are stronger and resist punctures better than plastic. Aluminium tends to dent and withstands more punishment. On a rebuttal side, I really don't see how a properly secured tank would be at risk, but during install this could be of concern.
One of the biggest issues in aluminium marine tanks are from builders foaming in the tanks. Aluminium tanks do not like moisture over prolonged periods, and the foam against the tank enables major corrosion to occur. The constant jarring of the boat eventually creates a seem between the tank and foam, which allows any moisture, whether from deck water running in or from simple condensation to do its damage. A properly mounted aluminium will have good airflow around all surface areas, thus allowing it to dry. Studies show that aluminium marine tanks are structurally sound for 10 years and in most cases longer
I have always been a fan of aluminum, as it's stronger, and as far as metal goes, I feel it is the best alloy for marine use hands down.
In relation to the medical factors, If I remember reading articles on this subject, (no pun intended) i think they may have been referring to users of aluminium saucepans, where the edges of the pan were constantly being scraped with steel spoons and the like - adding aluminium particles to the food. I'd read that the team that cut up and analysed the brains of old timers disease victims made a basic mistake by using aluminium contaminated instruments - but then again you can't believe everything that you read.
I believe the aluminium paranoia is unfounded. You cannot avoid it. Food processing, tanks, medicines, kitchenware, baking powder, flour, beer, cheese and salt even. The dust we breath has more aluminium in it than anything else. It's just silly. The medical problems are related to aluminum getting into the body thru dialysis or IV meds using impure water...not likely to happen on a boat. The paranoia started in the 1970's and never went away. To avoid aluminum is simple, just don't drink, eat or breathe.
I've had an 40 litre aliminium belly tank on my troopie for 10 years never had a problem - flush at least once a year and I'm fine .... Twitch ..... Twitch ..... Twitch ..... hahahahahahahahahahahaha
I also think with the discussion in the thread "Natures Head" of people pissing and shitting in the ocean, y'all have more diseases and contaminates to worry about than the so called "contaminates" from an ally tanks.
Roll the dice and take your chances. Do what you can afford and you'll be fine.
http://marinesurvey.com/yacht/fueltank.htm
iPad Forum Runner
The tank walls are 10mm thick and i have every confidence that they will work just fine without the risk of Crevice Corrosion. I'm not to concerned as to the so called "medical" disadvantages of aluminium tanks either
A correctly mounted aluminum marine fuel tank of high quality material, and under ideal conditions should outlast the boat. Some say they last 25-30 years, but I think they may go even longer as I've seen them past that mark and still in good shape. I've also seen some in the 15 year range that looked to be 50 years old due to crevice corrosion. Aluminium marine fuel tanks often have baffles in them to stabilise the fuel from swashing around excessively. Aluminum tanks are custom made, so getting one to match your boats design is a snap. A custom marine aluminium fuel tank can take advantage of extra space and allow for more fuel capacity. Aluminum fuel tanks are stronger and resist punctures better than plastic. Aluminium tends to dent and withstands more punishment. On a rebuttal side, I really don't see how a properly secured tank would be at risk, but during install this could be of concern.
One of the biggest issues in aluminium marine tanks are from builders foaming in the tanks. Aluminium tanks do not like moisture over prolonged periods, and the foam against the tank enables major corrosion to occur. The constant jarring of the boat eventually creates a seem between the tank and foam, which allows any moisture, whether from deck water running in or from simple condensation to do its damage. A properly mounted aluminium will have good airflow around all surface areas, thus allowing it to dry. Studies show that aluminium marine tanks are structurally sound for 10 years and in most cases longer
I have always been a fan of aluminum, as it's stronger, and as far as metal goes, I feel it is the best alloy for marine use hands down.
In relation to the medical factors, If I remember reading articles on this subject, (no pun intended) i think they may have been referring to users of aluminium saucepans, where the edges of the pan were constantly being scraped with steel spoons and the like - adding aluminium particles to the food. I'd read that the team that cut up and analysed the brains of old timers disease victims made a basic mistake by using aluminium contaminated instruments - but then again you can't believe everything that you read.
I believe the aluminium paranoia is unfounded. You cannot avoid it. Food processing, tanks, medicines, kitchenware, baking powder, flour, beer, cheese and salt even. The dust we breath has more aluminium in it than anything else. It's just silly. The medical problems are related to aluminum getting into the body thru dialysis or IV meds using impure water...not likely to happen on a boat. The paranoia started in the 1970's and never went away. To avoid aluminum is simple, just don't drink, eat or breathe.
I've had an 40 litre aliminium belly tank on my troopie for 10 years never had a problem - flush at least once a year and I'm fine .... Twitch ..... Twitch ..... Twitch ..... hahahahahahahahahahahaha
I also think with the discussion in the thread "Natures Head" of people pissing and shitting in the ocean, y'all have more diseases and contaminates to worry about than the so called "contaminates" from an ally tanks.
Roll the dice and take your chances. Do what you can afford and you'll be fine.
http://marinesurvey.com/yacht/fueltank.htm
iPad Forum Runner
Last edited:
psneeld
Guru
Epoxy composite is a possibility for custom tanks (water or fuel)...based on what aluminum fabricators are getting in the NJ area...I had even contemplated making my own fuel tanks to keep costs down.
There is a good discussion on building tanks using epoxy in the book, "The Gougeon Brothers on Boat Construction", 5th Ed. They do not recommend West System for potable water or gasoline tanks. Diesel, sewage and gray water have held up well using West System epoxy though.
