Backyard Aquaponics
A place to discuss aquaponics

Anyone with experience have any suggestions on the minimum thickness of pond liner for a grow bed? Thanks!!!

I have been wondering the same thing for a few days. Been searching Google and a few other forums, haven't come up with a minimum thickness or even a decent brand.

I use firestone pond guard. It is 45 mil (that's .045 of an inch). It works great when you don't drill a hole in it after intallation (which I did).

The minimum I have seen people using is 20mil but a 40-45 mil is going to last you a whole lot longer. I typically sell 40milHDPE or 45mil firestone PondGuard to my AP customers.

Will the 45mil will stand up to 3/4in gravel if its not from a river?

Yes, as long as it is supported properly. The 45mil pondguard is actually more flexible then the HDPE to conform over bumps and uneven surfaces in a newly dug pond(but as far as I know is not organically certifiable if that is what you are going for).

20-23mil will do the trick.

and at any rate, you're going to want to take precautions to protect your pond liner at any thickness.. people have used carpet scraps and even gone as low tech as to just put down a layer of sand before the put down the liner.

Thanks for the responses! I am building a 4 x 8 GB out of 2 x 12's and 1 inch plywood, raised of course. So should I cushion this?

just to be on the safe side everyones going to say yes. better to take precaution then to have to fix a mistake.

really if you can get rid of most of the bigger stones and then lay down some felt weed matting, you should be fine. the ground on the big island is primarily potato sized stones once you get past the thin layer of top soil, so leveling off the land exposes the larger stones. we just added some filler dirt on top of the stones, tamped it down, made sure no large sections of stone protruded through the soil, laid down weed matting, then build on top of it.

an easy way to check if it's going to harm your trough liner is to walk the ground bare foot. if the stones hurt your feet, they'll hurt the liner.

Look if you are going to use the Liner for a GROW bed.. cushion the underneath area and to make sure that you don't have any sharp stones penetrate the growbed when you load it up.. Try putting a layer or 6-7mm river pebble down say 1-2 inches..

If you are worried about the stones putting a hole thru the growbed put a second layer of the liner down[just the size of the bottom of the growbed] a double thickness should easy your mind..

Over all a layer of a smaller rounded stone should easy your mind on the issue of puncturing the liner..

Juergen

Digging up something from it's grave.


I've got some different views online with the pondliner.

I'm now looking to buy some myself

We'll be using 3/4 granite gravel quite rough stuff.

So i've seen people here reccomend 40+mills and somewhere else someone saying 20Mills will do.
My guess is these folks use hydroton what is smooth and easy.. Gravel ain't


Will a 40 Mill pondliner work for growbeds
(they will be in a steel frame, reinforced with plywood)

Your're not kidding there...