Fresh Water Tank Replacement

[zinahewitt]

Hi All,

Happy Holidays,
I have a water tank, it has started leaking some water from the top spout.
I was thinking of replacing it.
The last water tank I replaced, I went to a boat yard,
They charged me $900 for a flexible fresh water tank and freight. I googled it and it is $282 with free shipping.
They then charged me 6.5 hours of labor claiming they have to adapt my setup to fit the new tank.
In short $1800.
I was going to let them do the other tank 4 years later, but they said because of Covid and rising costs they wanted $3,000.

Obviously at a certain point, one says enough is enough.
Since I successfully replaced my poop holding tank and pipes for $500 of parts, I figure I can do this.

I have added the details.
My questions are.
1. When do you use the "vent", it is in the middle and you can twist it to "vent". I assume when filling the sack so you don't overfill it and explode it ?

2. My current one has an inspection port, the Boat Yard did not add one ?
Do you use it ? I read and some people will throw in baking soda once a year to sanitize it ?
Is it so you can reach in with your hand and clean the inside ?

3. I am on the Fence between VETUS and NAUTA. The Nauta is a little too big but it comes without any fittings installed.
In order to not have to redesign my current system, I need to install a fitting "under".
The Vetus comes with the fitting 38mm installed already.
I have asked them if they will sell me one without them installed but I assume they won't.
So my question is.
Do i just get the VETUS which is what the boat yard put, cap the 38mm on top {if so how}, but another one install it at the bottom and voila ?
Or do I get the NAUTA. The Nauta doesn't seem to have an inspection port, but it does have the vent.


Thank you for your time.

 

[Captain Larry-DH]

I have some of your answers but also have questions:
Why replace the whole tank when the top fitting is leaking? Precisely what is causing the leak? Can that be repaired without tank replacement? What is your original tank made from? Photos would also help.
Why use flexible tanks? You can buy custom heavy duty plastic tanks for a similar price that will last longer than your boat. Manufacturer Of Plastic Tanks, RV Tanks, Storage Tanks – Ronco Plastics

 

[zinahewitt]

I have some of your answers but also have questions:
Why replace the whole tank when the top fitting is leaking? Precisely what is causing the leak? Can that be repaired without tank replacement? What is your original tank made from? Photos would also help.
Why use flexible tanks? You can buy custom heavy duty plastic tanks for a similar price that will last longer than your boat. Manufacturer Of Plastic Tanks, RV Tanks, Storage Tanks – Ronco Plastics

Hi Larry, hope your day is going well.

Boats being boats, the shape of the area where the tank sits is not regular.
I'd have to get a custom tank made and shipped, that ends up being 3-4 times the price.

The tank is around 30 years old or more.
The leak is when the the tank is full and the hose pulls a bit on the fitting. Looks like over time it has stretched the area.

I might be able to pull the tank out, then remove the fitting, then seal that area completely and make a new cut and put a new fitting in and then resize the hoses, but I did not have luck fixing the other tank last time, the glue did not catch well on the material.

 

[Ralph Johnstone]

Why use flexible tanks? You can buy custom heavy duty plastic tanks for a similar price that will last longer than your boat. Manufacturer Of Plastic Tanks, RV Tanks, Storage Tanks – Ronco Plastics

WHY would you look at a flexible tank ?

Take charge of this job, stop getting ripped off, and do it right ! ! ! !

 

[higgs]

Ronco makes plastic tanks in a vast assortment of sizes and shapes. As for the purpose of a vent, it is needed to let air flow freely. Otherwise a vacuum will form when using water. When filling, air needs to get out of the tank to make room for the water. An inspection port is good to have because mold can build up in water tanks. I have not heard of using baking soda to clean the water. I always threw a cup or two of bleach in with the water.

Water / Waste Holding Tank - Ronco Plastics

Marine tanks are suitable for all marine plumbing, waste holding, and water supply needs. The tanks are rotationally molded of a seamless one piece, non-corrosive linear polyethylene and meet FDA regulations. Three female NPT up to 1 1/2" (national pipe thread) fittings are provided free of...

ronco-plastics.com

 

[MikeHoncho]

Ronco makes plastic tanks in a vast assortment of sizes and shapes. As for the purpose of a vent, it is needed to let air flow freely. Otherwise a vacuum will form when using water. When filling, air needs to get out of the tank to make room for the water. An inspection port is good to have because mold can build up in water tanks. I have not heard of using baking soda to clean the water. I always threw a cup or two of bleach in with the water.

Water / Waste Holding Tank - Ronco Plastics

Marine tanks are suitable for all marine plumbing, waste holding, and water supply needs. The tanks are rotationally molded of a seamless one piece, non-corrosive linear polyethylene and meet FDA regulations. Three female NPT up to 1 1/2" (national pipe thread) fittings are provided free of...

ronco-plastics.com

Vents are not required for flexible bladder bags except to tell you when it is full. Having one will also allow total filling of the bladder by evacuating any air pockets but its not a significant amount.

 

[Peggie Hall HeadMistress]

+1 for the suggestion to explore a Ronco Plastics rigid tank. They're top quality, reasonably priced, install fittings in the sizes and locations specified by the customer...and have 400+ shapes and sized in their catalog.
Ronco Plastics Water and Waste Holding Tanks catalog
Ronco Plastics marine Tank drawings
When looking at the drawings keep in mind that there is no top or bottom until the fittings are installed and you decide where they go. So rotate, flip, reverse fore-aft...you're almost guaranteed to find one that'll fit your space, or another space that'll work.

--Peggie
I just looked at your photograph...the only thing that MAY create a problem finding a Ronco tank that'll fit that space is its depth...I can't tell from the photo how deep it is. And you may have to settle for one that's a bit shorter than the entire space. Yes, it will need a vent.

 

[Captain Larry-DH]

Hi Larry, hope your day is going well.

Boats being boats, the shape of the area where the tank sits is not regular.
I'd have to get a custom tank made and shipped, that ends up being 3-4 times the price.

The tank is around 30 years old or more.
The leak is when the the tank is full and the hose pulls a bit on the fitting. Looks like over time it has stretched the area.

I might be able to pull the tank out, then remove the fitting, then seal that area completely and make a new cut and put a new fitting in and then resize the hoses, but I did not have luck fixing the other tank last time, the glue did not catch well on the material.

You didn't answer any of my questions about your original tank. I gave you good advice as did others on this thread. Your picture looks like it would be an easy replacement for a Ronco tank. Peggie gave more info about them.
I've replaced a tank with a Ronco and they really do provide a quality product and they know their business. It's the right way to go based on your picture, and it's not as expensive as you may think. However if you'd get back to the original questions you might find that you receive the same advice you already got OR you might learn about how to repair the leak in what you've already got without need for replacement.

 

[Scott T-Bird]

I'd bet there is a tank fabricator near enough for you to have a custom tank made at an affordable price. When I replaced my aluminum water tank, I had a custom stainless steel tank made for about $350 for a 15 gallon tank. It came with a certification for its use. Granted, I wasn't able to get a plastic tank. I preferred not to get an aluminum tank for use with potable water (my original water tank was aluminum and I was disturbed by the white corrosion residue left in the bottom). I looked thru the Ronco selection (hundreds of them) and found nothing that was a close shape to the one I had. I was thinking that a replacement might be impossible. Then, I just googled "tank fabrication" and found Patriot Marine Fabricating in Forked River. They could not have been easier to work with. I gave them dimensional drawings for the tank I wanted and they provided a reasonable estimate. They fabricated it perfectly, I got it quickly, and the price was perfectly reasonable. They have made an aluminum fuel tank and a stainless steel water tank for my boat and it was a great experience to work with them.

 

[zinahewitt]

I'd bet there is a tank fabricator near enough for you to have a custom tank made at an affordable price. When I replaced my aluminum water tank, I had a custom stainless steel tank made for about $350 for a 15 gallon tank. It came with a certification for its use. Granted, I wasn't able to get a plastic tank. I preferred not to get an aluminum tank for use with potable water (my original water tank was aluminum and I was disturbed by the white corrosion residue left in the bottom). I looked thru the Ronco selection (hundreds of them) and found nothing that was a close shape to the one I had. I was thinking that a replacement might be impossible. Then, I just googled "tank fabrication" and found Patriot Marine Fabricating in Forked River. They could not have been easier to work with. I gave them dimensional drawings for the tank I wanted and they provided a reasonable estimate. They fabricated it perfectly, I got it quickly, and the price was perfectly reasonable. They have made an aluminum fuel tank and a stainless steel water tank for my boat and it was a great experience to work with them.

Hi Scott,
Unfortunately this is the Bay Area of Silicon Valley in California.
so no one here offers reasonable prices for anything.
No one here will custom make a tank for $350.

 

[zinahewitt]

You didn't answer any of my questions about your original tank. I gave you good advice as did others on this thread. Your picture looks like it would be an easy replacement for a Ronco tank. Peggie gave more info about them.
I've replaced a tank with a Ronco and they really do provide a quality product and they know their business. It's the right way to go based on your picture, and it's not as expensive as you may think. However if you'd get back to the original questions you might find that you receive the same advice you already got OR you might learn about how to repair the leak in what you've already got without need for replacement.

Hi Larry,

Hope all is going well.
You asked.
"""

I have some of your answers but also have questions:
Why replace the whole tank when the top fitting is leaking? Precisely what is causing the leak? Can that be repaired without tank replacement? What is your original tank made from? Photos would also help.
Why use flexible tanks? You can buy custom heavy duty plastic tanks for a similar price that will last longer than your boat
"""

Why replace the tank, the tank is very old and leaking,
The leak is caused by the fittings wearing out the tank.
I can't repair the tank due to age and the material losing original texture.

What is the material ? I can't tell, there are no markings. I assume some Material that was available in the 1975s.

Why use Flexible tanks?
The shape that holds the tank is something like the images I added.
Ronco does not make that shape and because most of the tank is on a slope if I use a square that does not sit on the bottom with the weight of the water it will push on the
wood piece you see next to the cushion.
A few times the boat will go up and down in crashing wave action and the weight of the box will push and tear the wood out.
The flex while crappy and needing to be replaced lies comfortably on the bottom of the area and I can bolt it to the side of the boat with Weld mounts. It also spreads the load around.
A Custom tank is an expensive option here and online would require expensive shipping.

Happy Holidays.

 

[FastOlson]

I have bought and installed a Ronco tank. They do have a variety of shapes including some with a sloped bottom.
That said, I did have one custom plastic water tank welded up to fit an area that would not accommodate one of the cataloged sizes. I found a local tank builder who built it using a technique called hot-air-welding. Worked like a charm. He built to my drawing, after I built a mockup and made the drawing from that.
So you might want to check around for that option, as well. I found my guy thru the manager of a local boat yard.

Another answer: I also have a different water tank constructed from SS, to my drawing similar the diagram in reply 11. I found a job shop that specialized in SS work. He had a background in "brewery grade" SS tank building, so it was easy for him. It is heavier than my plastic tanks, tho.

 

[zinahewitt]

I have bought and installed a Ronco tank. They do have a variety of shapes including some with a sloped bottom.
That said, I did have one custom plastic water tank welded up to fit an area that would not accommodate one of the cataloged sizes. I found a local tank builder who built it using a technique called hot-air-welding. Worked like a charm. He built to my drawing, after I built a mockup and made the drawing from that.
So you might want to check around for that option, as well. I found my guy thru the manager of a local boat yard.

Another answer: I also have a different water tank constructed from SS, to my drawing similar the diagram in reply 11. I found a job shop that specialized in SS work. He had a background in "brewery grade" SS tank building, so it was easy for him. It is heavier than my plastic tanks, tho.

Hi,
I looked at the ones that were close and had a sloped bottom. Those would be pushing against the wood side too , so eventually the wood would give with 45 gallons of water + tank weight pushing against it while the boat is heeled and smacking into waves going up wind.

I'll ask around for people who work hot air welding.
I can't see to get any hits on google in the bay area.
I am guessing based on watching a few videos that the tank was not cheap.


Stainless steel seems like an overkill for a 34' 1970s boat.