Backyard Aquaponics
A place to discuss aquaponics

many weldable plastics are used and accepted for wrapping foods. Surely one of these should be convenient as a liner
Frank

There are a number of pond liners which are considered to be safe Frank.

maybe put an inner liner into the outer one, if the food grade material should not be strong enough? I am merely thinking out loud
where should we look for this material?

Strenght is not a major issue with the ones I am thinking of Frank - though they are not cheap.

Dunno about in your country - but some pond shops sell them here.

http://www.creativepumps.com.au/Pumps/P ... _liner.htm

EDPM or Xavan are the ones I would consider most food safe. EDPM is more flexible.

be aware that just cause the pvc liner states "non-toxic" doesn't mean food grade..............

Notice that the XAVAN goes one step further and states "Chemically neutral (no leaching) - Non toxic"

its my plan to do exactly this, i have acces to old galvanised tanks that have rusted out in places but are still structuraly sound and will be lining them with a pond liner (probabaly xavan )

seems like a really cheap way to go to me and you can then make your tank any shape you like

i have used the EDPM and like it. a compromise between pvc and xavan

I have professionally been building cleaning systems for the food industry, and EPDM (not EDPM, unless the english abbreviative is different) seems indeed an excellent choice. I used it for all kinds of gaskets, and solved a lot of leak problems occurring with other industrial rubbers (i.e. Buna M, the most used rubber for O-rings). It is as good as chemically inert, which means it won't be attached by most chemicals.
To proceed in the thread, I have also sent an e-mail to the pool manufacturer's representative, explaining our concerns about PVC toxicity and asking for a food grade liner. I am awaiting a reply.
Frank

Frank, just checked, it is indeed EPDM