Fiberglass water tanks/fuel Tanks...Thoughts?

[mattdana78]

Welcome the input of those with DIRECT experience with fiberglass tanks here, not speculation or second hand hearsay:

Our new (to us) yacht has integral fiberglass tankage.
Domestic water filtration is already in place.
We are sending out water for testing tomorrow.
Looks super clean upon inspection and there is no odor etc etc.

Do other yacht owners with this setup drink the water? Cook with the water?

Look forward to your experiences.

mtd

[Pitchondesign]

I have had two boats with integral fiberglass tanks. My current boat is 29 years old and the tanks are fine. I have had the inspection plates off and they look was new. My previous boat was the same.

[rsn48]

Almost all RV's have fiberglass holding tanks of all types.

[Emmalina]

If it was built with epoxy Not polyester then no problems

[DougR]

Back in the 70's I owned Tartan 30s which had water tanks which were made as an integral part of the fiberglass hull liner. Supposedly these were made with what was called " sanitary" gel coat. The construction was a rectangular recess in the liner with a plastic coated plywood cover caulked and screwed down over the recess. About 30 gallons if I recall.

At that time I didn't have any sort of filtration system in place so there was almost always a slight taste of fiberglass to the water. Still, we washed with it, cooked with it and drank it, and lived to sail another day....

DougR

[thinwater]

I've had FRP tanks (water, waste, and gasoline). No problems.


The water tests won't tell you anything about the FRP unless they are given very specific instructions to look for monomers. Standard water tests will reveal nothing.

[DougR]

For years and years Bertram Yacht used fiberglass fuel tanks in their big sport fishing boats without problems.

A well made fiberglass diesel tank shouldn't give any problems, particularly if today's epoxy resins are used.

DougR

[coopec43]

I've made up my own tanks and coated them with a product approved by the WHO for potable water (Standard AS4020).

The supplier of polyester resin stated that f/g is unsuitable for potable water unless coated. There are many products that claim to be suitable by the Distributors but they must be cured in optimal conditions and we amateurs cannot provide those conditions. West System advise against amateur built epoxy water tanks (There are plenty of articles on the internet explaining why)
"Aug 24, 2011 - Epoxy water tanks have been around for more than four decades, but it is notable that West does not recommend epoxy for drinking water tanks ..."
https://www.sailmagazine.com/diy/epoxy-in-water-tanks


If the tests come back OK then you do not have a problem. But I have followed Jim Skoog's advice (Cruising in comfort) and he says all tanks should be removable for maintenance and all parts of each tank should be accessible for regular cleaning and flushing.

[coopec43]

Gougeon Bros West System

Why we don’t recommend building an epoxy composite tank for potable water We have adopted the broad policy of not recommending epoxy f....

https://www.epoxyworks.com/index.php...ank-guidelines

[blubaju]

>20 years all water and diesel tanks epoxy. The drinking water tank is additionally painted with food grade epoxy paint (Jotun). Gasoline for the outboard remains in plastic jerry cans, 2x 10kg propane in GRP bottles

[coopec43]

Apr 16, 2018 - Goodwin says that fiberglass is ABYC-approved for diesel, if the proper high-spec, flame-retardant resin is used. Early fiberglass tanks were ...

https://www.powerandmotoryacht.com/m...s-on-your-boat

[Sailor647]

Originally Posted by coopec43

I've made up my own tanks and coated them with a product approved by the WHO for potable water (Standard AS4020).

The supplier of polyester resin stated that f/g is unsuitable for potable water unless coated. There are many products that claim to be suitable by the Distributors but they must be cured in optimal conditions and we amateurs cannot provide those conditions. West System advise against amateur built epoxy water tanks (There are plenty of articles on the internet explaining why)
"Aug 24, 2011 - Epoxy water tanks have been around for more than four decades, but it is notable that West does not recommend epoxy for drinking water tanks ..."
https://www.sailmagazine.com/diy/epoxy-in-water-tanks


If the tests come back OK then you do not have a problem. But I have followed Jim Skoog's advice (Cruising in comfort) and he says all tanks should be removable for maintenance and all parts of each tank should be accessible for regular cleaning and flushing.

We agree with all of the above.

We are in the finishing stages of lining our 50 gallon and 70 gallon water tanks with fiberglass.

The tanks were original, 31 years-old, too-large-to-remove, stainless steel, and built in. The welds began rusting and developed pinhole leaks. The whole process was a huge undertaking, but it didn't destroy the interior of our boat or decrease our tank capacity (by much).

Because the fiberglass leaches chemicals into the water - which you can easily taste (we did), and the .4 micron filter won't remove (we tried) - we are painting the entire interior surface of the tanks with Liquitile 1172.

LiquaTile 1172 - Epoxy Manufacturer: Wolverine Coatings Corporation

This UL coating is drinking-water safe for tanks 50 gallons and larger. We know of another sailor who lined his original-to-the boat integral fiberglass tanks with this product. They are raising small children on board and didn't want to take any chances with water contamination. Three years later, so far so good.

Good luck!

[lask]

in boats like mine (atlantic 31) the water tank is built with fiberglass and inside jellkoat, it's wrong finally because a few years ago when I opened to clean it with (chlorine) I saw that it was osmoticated to a great extent so I built a tank with pvc (flexible). I think that if it is not with epoxi paid internally it is dangerous

[Group9]

Originally Posted by DougR

For years and years Bertram Yacht used fiberglass fuel tanks in their big sport fishing boats without problems.

A well made fiberglass diesel tank shouldn't give any problems, particularly if today's epoxy resins are used.

DougR

We have a 1973 Bertram. The original fiberglass diesel fuel tanks are still in great condition.

[MJH]

Originally Posted by mattdana78

Welcome the input of those with DIRECT experience with fiberglass tanks here, not speculation or second hand hearsay:

Our new (to us) yacht has integral fiberglass tankage.
Domestic water filtration is already in place.
We are sending out water for testing tomorrow.
Looks super clean upon inspection and there is no odor etc etc.

Do other yacht owners with this setup drink the water? Cook with the water?

Look forward to your experiences.

mtd

My 1979 Tayana Vancouver 42 has 2x75 gallon diesel fuel tanks, 1x45 gallon holding tank, and 1x12 gallon sump tank...all of them fiberglass. The boat is celebrating its 40 birthday this year. There have been no leaks but the holding and sump tanks have been re-tabbed to the hull. The tank capacities as well as the material were positives for me buying the boat. FWIW, the water tanks are 2x100 gallons stainless steel, also without leaks. I'm very pleased with the arrangement.

~ ~ _/) ~ ~ MJH