Sealing integral water tanks

[Antipodean2]

G’day
I have needed to do a some work on my water tank">fresh water tank, it had a slow annoying
Leak albeit it slow I have tried to stop it from causing further damage.
Whilst empty and dry I gave the interior of the tank a coating of odourless and tasteless food grade epoxy after 2 coats and applying dynel to possible areas of concern, allowed it to cure for 2 weeks before refilling with water.
The first wash out tasted of Zylene , emptied the tank, air dried and refilled it again the second wash still has a epoxy taste.

Has anyone had any experience with sealing epoxy water tanks?

I have 3 current options at the moment
1. Coat interior with West Epoxy Flowcoat
2. Use liquid rubber paint
3. Install a bladder ( last resort) as major modifications required.

[japawil]

What “odourless and tasteless food grade epoxy” did you use, and did you apply the dynel before or after?

[Antipodean2]

Hi
It was AA Composites epoxy for manufacturing used the same resin for the dynel
It did take around 48 hours to go off and I mixed it to the correct specs of 3:1

[BlueH2Obound]

drain and fill about 4 or 5 times. It would help if the tank were 90% full and you went out and sloshed it around a little. Put a cup of household bleach in each time. Taste should get to the tolerable stage after a half a dozen iterations or so.

[Jammer]

All epoxies will leach chemicals into the water.


Many formulations previously listed as "food grade" in the USA have been delisted or restricted to larger water tanks (where the ratio of volume of water to area of epoxy is more favorable) due to a growing realization that BPA and other leachates are toxic at lower levels than previously believed.


In many cases with older molded-in-place tanks there is no solution now considered safe for drinking water.

[japawil]

I was researching for just the same sort of problem and as Jammer indicated, couldn’t find any epoxy approved for use in potable water tanks under a few hundred gallons.

I then came across a product called Microseal that is actually advertised for use in boat’s water tanks.
It’s made for penetrating micro cracks and imperfections in castings.
It can be brushed, sprayed or dipped.
I got some to try out, but have not yet had the chance to use it, so I can’t vouch for it.
It does sound like the ticket though.
http://microleak.com/product-application/ http://microleak.com/wp-content/uplo...ankarticle.pdf

[Antipodean2]

I read the article on micro seal , sounds good , thanks