NANFA-- RE:pond liners

Nicholas J. Zarlinga (
Fri, 23 Mar 2001 20:05:45 -0500

Just an FYI that I have recently found out. Be very carefull with roofing
materials as pond liners! I have been working on this with a friend of
mine and have conducted some simple experiments. The problem with roofing
material is that when you cut it, you must take caution to not let the
exposed cut come in contact with the water in the pond. The roofing
material is made up of a number of chemicals which are very toxic to
aquatic animals. I did not believe it myself when a friend told me that he
thought that this was a problem. So to prove it to him, I set up a couple
of 10 gallon tanks and put a half a dozen feeder goldfish in each. I
waited several weeks so that I knew that the goldfish were acclimated and
the tanks were cycled. Then, I freshly cut a couple of 8 x 10 inch squares
and put each of them in the 10 gallon tanks. To my surprise, the very next
day the tanks that had the squares of roofing materials in them had dead
fish and the ones that were alive looked horrible. The goldfish in the
control tanks looked perfect. I did the same experiment a second time with
the same pieces of material that had a week or so to cure and the fish were
fine. One other thing to beware of. There are pond liners which are said
to be pet safe which are not. Only a couple of manufaturers make rubber
liners and they are the same manufacturers which make the roofing material.
The roofing material is obviously cheaper and many pet companies purchase
the roofing material and pawn it off as pet safe liner, which it isn't. Be
very careful to either test the roofing material or at least let the cut
edges cure before using in. Has anyone else had bad experiences with
roofing material?

Nick Zarlinga

.??`..,. , . ..??`... ><((((o>`..,,..??`..,..??`....,><((((o>

"Fish worship...Is it wrong???" (Ray Troll)
> ------------------------------
> Date: Fri, 23 Mar 2001 10:20:37 -0600
> From: "R. W. Wolff" <>
> Subject: Re: NANFA-- gar pond
> I built a filter last year and ran it off a different pump, but it only
> worked for a while. There is a prefilter on the pump, a sponge, but other
> than that there is no filtration other than plants. When I do the last
> addition this spring, I will be adding another pump, and a weedy stream
> to help filter the water. The sheets are left overs from jobs. I think
> biggest single sheet I ever got was 25' X 25' . The gar pond has a seam
> between the two points. To seam it I used that rubber tape with the tar
> like stuff on the back, the same stuff they seem the roofs with. Its
> and better quality than the stuff they sell in catalogs for pond use or
> pond/ garden centers.
> Ray
> > Are you
> > running some sort of filter with the pump or are you just using it for
> > circulation.How big does the roofing material come? Did you have to
> it
> > for a pond that big.
> > Jim Graham
> > Hastings, Mi

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