pond liners have a 20 year warrenty and tarps don't. There is a cost difference, but you have to weigh the added cost with the work involved in changing the tarp again in 10 years or so. A potential problem I see with tarps is that many are treated with anti-fungal agents although they may not list that on the label. They don't have to....the tarp was not designed for use with fish. Anti-fungal agents will kill fish quick. I know a young man who used furnace filters in his pond filter and all his fish died over night. After further investigation with the company who made the filters, it turns out they were treated with fungacides and that's why the fish died. Be careful using non-fish related items in a pond.

Hi
Well, the tarp is still not leaking after 17 years lol
It has outlasted the 4x4's I kept fish in it for over 15 years but the tarp didn't stop raccoons .lol
Have often heard the the limits you mention just haven't found them to be true .
Interestingly I built this pool in ignorance with materials I had on hand. Had i read all the writeups on it I probably wouldn't have done it lol.
Unless I hear some better arguments think I'll use the tarp and get some new fish with the 35 bucks lol Thanks for the reply gary

Not sure why you asked for opinions when you had no intentions of following any of them. If it worked for 17 years, by all means do it again. Good luck

Hi
My mistake thought this was a forum for discussing all methods?? I asked because I know for a fact the usual negatives don't hold up .Thought there must be something I'm missing. Maybe it might help someone looking for alternative methods.?? Thanks for your permission to use the methosd lol gary

I think I pointed out a very real possible negative....the possibility of the tarp being treated with anti-fungal agents. Some are, some are not, most are not labeled. I personally would not risk my fish to save $35.

I didn't intend to get your dander up... Now that you know the negatives and you go ahead with the tarp and if it is one with harmful treatment and you have saved $35 so you can buy some fish and find them dead soon after introducing them to contaminated water. What have you really saved?? Glenda

Hi Gary.

My first attempt at a pond was when I was a little kid a thousand years ago. We used a tarp. It lasted years (don't remember how many) but the pond was doomed when a thunderstorm resulted in the Weeping Willow Tree tossing a spear-like branch right into the heart of the liner .... killing it instantly. Not even a bazillion dollar pond liner would have survived the assault.

Now we use a pond liner rather than a tarp simply because we think it will endure our winter weather better than a tarp. You don't have the same issues. I dunno ponds and the technical thingies about them but sometimes I can pretend.

If it ain't broke don't fix it. :-)

Glenda
I'm old my dander is always up.lol In the pond with the tarp I kept fish in it for well over ten years. .
I used the tarp because I had it to keep the roof from leaking and then decided to make a pond with it mostly for plants fish were added much later. I built it without ever reading a word lol.
The only reason I'm replacing it now is because of the weeds. The marshmallow has rooted to the sides and will be impossible to remove. .Also the 4x4's are crumbling in places so it's no longer level. Think i might also add some tile to the exterior to dress it up a bit. Just time for a facelift lol
Anyway , have been doing a lot of reading and never found one mention of a tarp as a liner and was curious as to why since I know they work. My only objection to the liner is that it is a silver color.
I intend to expand the shadehouse over this pool and use it for a winter heat system and since it will be protected from birds and heated thought I might raise either discus or angel fish in it as well as plants. May be wise to go with a regular liner for this reason.
Chick 3 d I'd bet freezing would make a big difference in the longevity of the liner. Have no experience with that only get a frost about every 5 years never a freeze. besides it will be heated now anyway.
Anybody have an idea of what kind of chemicals that might be used that would be toxic?? The tarps I'm looking at are fiberglass reinforced polymer resin. have no idea what the original is made of . What do they use to make them UV resistant?? Thanks for the input!!!
Thanks gary

Gary, I too am old if you call 64 old. I was wondering what Marshmallow was except the kind you eat. When you mention fiberglas, this rings a bell... I read somewhere on the the forum,in the past and don't remember when or where. There was a caution, in regard to filter material not to use furnace filters because they contained fiberglas. I would check that out from that standpoint. I also built my first pond with almost no information on pond building. We made lots of mistakes that caused us a lot of extra work, backaches and anguish. Then we took the time to plan and figure out exactly what we wanted and with information I gleaned from others on this forum, now in my opinion have the perfect pond. "that is for me". Only thing is I have a retrofit BD and wish that we had gone to the extra trouble to put in a regular BD. But what I have seems to be working. Good luck on whatever you decide. Glenda

You said that the tarp worked for 17 years, that means you bought it at least 17 years ago.I would call the tarp company and make sure that there are no chemical treatments done to their tarps now. Many products have changed in 17 years ie: fire retardent chemicals added to blankets.Do alittle research...better safe than sorry. Good Luck susie

Hi
Glenda You don't have the yellow flowered mallow with the fuzzy leaves in your area?? I really don't know the name of it but it is in every swamp in Palm Beach county.. I know it's a mallow and it lives in a marsh so I call it Marshmallow lol. It sprouts right at the water line and as long as there's water it will grow lol. If you don't have these you're very lucky.
Susie The tarp was given to me by a neighbor and was used as a temporary patch on the roof . After putting on the new roof I made the pool out of the tarp. No idea who the manufacturer.was. Except for the color silver it looks like the ones i see at wallies.Woven Fiberglass threads covered with a seal of some kind.
Have not kept fish in it ,not because of deaths but Herons and Raccoons.lol I have kept swordtails and platies in it for many years. The Herons eat these also but they breed faster than they can feed lol.
I find it very difficult to learn the toxicity of material unless a product is made specicly for the purpose.
If I go for the discus or angelfish I probably should go with the regular liner as obviously I'll want to have better water quality as well as keep it on the acid side.
thanks again gary

Gary, No we don't have that kind of weed, Thank Goodness. The worst thing we have is Devil's Shoelace everywhere. Not at the pond though. It got spread from putting peat around plants. Don't know where it came from before that. As you know every pest, plant or insect was introduced to Fla. as a cure-all for some other pest. I can imagine you having a Heron problem there. They are bad enough here. We built my pond with straight deep sides and I use a net most of the time on my pond to keep them out. Each one of my fish is like a personal friend and I am determined to keep each one of them safe. Glenda