Stainless Steel vs Polyethylene Water Tanks

[Cal 43]

We are replacing the 39 yr old stainless steel tanks on our Cal 43 Summer Wind. Any thoughts about the advantages/disadvantages of Stainless Steel vs Polyethylene?

Rhonda

[skipmac]

Well if you can get the new tanks fabricated to fit and don't mind the extra expense I personally prefer SS. Poly to me always imparts a taste to the water that you would not get from SS. If the old ones lasted 39 years and the new ones are made as well then they should last the life of the boat.

Just for curiosity, why replacing the old ones? If a split seam or something why not weld them and keep them?

[Zednotzee]

I'm thinking of replacing my tanks with plastic in the next few years. There are no corrosion issues & they're lighter. There may be a slight taste imparted by some products when new, but it should fade over time. I believe they are cheaper as well, & can be manufactured in a wider variety of shapes, complete with fittings.

[s/v Jedi]

How about wood-epoxy-glass composite? can easily be done DIY and in any shape you like. Strong, stiff and non-metallic.

cheers,
Nick.

[Cal 43]

The exisiting tanks were very well built but now have a few scattered pinholes and one corner that has just recently corroded through. Not bad for 39 years of service! However, there is only one small fill hole in each tank - NO inspection ports and no way to see inside, much less clean out properly. Yuck.

Does anyone out there have older plastic tanks? How have they held up over years? Does the taste eventually go away? Have you been able to sanitize them properly?

In a previous boat, I had a fiberglass tank that blistered & the idea of drinking epoxy is not appealing.

[s/v Jedi]

Originally Posted by Cal 43

In a previous boat, I had a fiberglass tank that blistered & the idea of drinking epoxy is not appealing.

The tank in that previous boat was fiberglass + polyester resin. When you use epoxy, you spend more money but you will not get blisters. Also, after the epoxy is cured, you can't drink it anymore ;-) and cured epoxy is inert.

Most treatments for inside water tanks are epoxy based (cement is the only one that isn't that I can think of).

My water tanks are fiberglass + vinylester resin, which isn't as good as epoxy. They are 15 years old, spotlessly clean and without any funny taste to the water.

After you build an epoxy tank, scrub the inside with water and a scoth-pad to remove amine-blush and the tank will be good for the life-span of the boat. I can't think of any better choice and I can't think of any easier to build it yourself choice.

ciao!
Nick.

[Efraim]

Originally Posted by s/v Jedi

The tank in that previous boat was fiberglass + polyester resin. When you use epoxy, you spend more money but you will not get blisters. Also, after the epoxy is cured, you can't drink it anymore ;-) and cured epoxy is inert.

Most treatments for inside water tanks are epoxy based (cement is the only one that isn't that I can think of).

My water tanks are fiberglass + vinylester resin, which isn't as good as epoxy. They are 15 years old, spotlessly clean and without any funny taste to the water.

After you build an epoxy tank, scrub the inside with water and a scoth-pad to remove amine-blush and the tank will be good for the life-span of the boat. I can't think of any better choice and I can't think of any easier to build it yourself choice.

ciao!
Nick.

Just to add to the above post. There are all types of "food grade" epoxies out there, made specifically for water or food storage containers.

[Vasco]

Originally Posted by Cal 43

Does anyone out there have older plastic tanks? How have they held up over years? Does the taste eventually go away? Have you been able to sanitize them properly?

.

The polyethylene tanks in my CS36M are 21 years old. Still as clean as new and no taste whatsoever. I once had to put a bit of bleach in them to clean after getting a load of bad water. I've now learnt to fill a bucket before my tanks in strange places. The tanks are a snap to clean. And you can see the level of water in them, no need for guages.

[Maren]

Originally Posted by Efraim

Just to add to the above post. There are all types of "food grade" epoxies out there, made specifically for water or food storage containers.

And there are food grade polyethelenes. Sorry we're not making this any easier.

[s/v Jedi]

Originally Posted by Maren

And there are food grade polyethelenes. Sorry we're not making this any easier.

Yes we do... if he can fit a standard sized polyethelene tank and the price is right, that's the path to walk. If the standard shapes don't fit or more capacity is required for which odd shapes are needed: custom epoxy is the path.

ciao!
Nick.

[Maren]

Originally Posted by s/v Jedi

Yes we do... if he can fit a standard sized polyethelene tank and the price is right, that's the path to walk. If the standard shapes don't fit or more capacity is required for which odd shapes are needed: custom epoxy is the path.

Assuming he doesn't check out that link to the vetus e-tank I posted on another thread, the one with the flexiable tank that hardens and has a food grade polyethylene liner.

whoops.

[Vasco]

These guys will supply custom polyethylene tanks.
Holland Marine Products