How to Affix Pebbles to Sides of Rigid Plastic Liner 04/22/08
Hello, Crew:
<Angie>
We have a rigid pond liner from Lowe's - kidney shaped, approximately 6' x 3'. After sustaining a bullet hole last summer, midway down, the pond developed a leak.
<I'll bet!>
We removed the pond and treated the outside with a gallon of asphalt roofing sealant, paying special attention to the hole.
<Mmm, won't "do it">
On the inside, we would like to affix pebbles from the lip down to the plant shelf in the hopes that this will offer a more natural look on the sides when the water level is low due to evaporation, etc. I have been told not to use the roofing asphalt as "grout" due to fish toxicity. We plan on having only a few goldfish and water plants. Is there another inexpensive product that will adhere the pea pebbles to the rigid plastic? Cost is a major factor.
Thank you very much for your expertise,
A.
<I'd look about (maybe Pier 1 Imports) for some of the "already affixed" material that I've seen sold as "place mats"... Last time was in Laguna Beach, CA (last week) at a gift shop... and cut and hang this material that already has these "wampum stones" affixed (I think with "glue gun" material or some sort of serious epoxy. Otherwise, you can try affixing them yourself... with the liner up, out, laid out and dried... with 100% Clear Silastic... will take a while to set, cure... Bob Fenner>

Pond liner exposure to winter weather 10/14/07
We drain our 4000 gallon pond and would like to leave it empty for the winter. We want to leave it empty and then clean and refill it in the spring. All fish and plants have been relocated to another pond.
Will this cause any damage to the pond liner since it will be exposed to cold central Illinois weather?
<Mmm, likely not IF this liner is of butyl/rubber... EPDM or composite make-up of adequate thickness (30 mils or more let's say)... I might throw some straw on it to prevent some possible damage by accrued snow, water/ice. Bob Fenner>

Pond question - 8/17/07
Mr. Fenner-
<Mr. Agins>
I recently installed a pond with approximate nominal dimensions of 13'L x 16'W x 2.5' D. Because of the rounded corners, and such, it is less than the 3900 gallons the dimensions would imply, perhaps by 20%. So, let's say that it's roughly 3000 gallons. The pond is EPDM lined with EasyPro aquafalls at the head, and skimmer on the wall opposite the waterfall. The waterfall feeds a stream approximately 3'W x 10'L x 9"D. I am using a PondMaster 5000 GPH mag drive pump.
<Okay...>
When I first assembled everything, following the manufacturer's directions for through-the-liner installation of the skimmer weir door, the water level drained to exactly the bottom of the weir, leading me to conclude that the weir connection was the culprit.
<Likely so>
I called the supplier from whom I bought the materials, who told me that silicone would not adhere to EPDM
<This is correct>
(contrary
to the manufacturer's instructions) and to use EPDM caulk for the connection. When I called my local roofing supplier, they told me that EPDM caulk is just a temporary material and, instead, to used a particular waterproof EPDM tape.
<If the space/gap is very small, this may work...>
I have applied this tape - very carefully, after cleaning the EPDM liner with a solvent and rolling the tape with a roller after application - but still notice a slow drop in water level. I have checked the seam where the stream liner meets the pond liner and have re-taped that junction, also. When I turn off the pump (which has a check valve in the line to prevent backflow), the Aquafalls remains full, leading me to believe there is no leak in the bulkhead fittings or the flexible PVC connection to the Aquafalls.
<Seems reasonable>
The run of flexible 2" PVC connecting the skimmer to the Aquafalls is about 30' long and runs 8-10" below ground level, in newly laid topsoil. I don't see any evidence of wet ground around the path of the PVC tubing.
Question (after this very long preamble): Is it possible that the drop in water level could be the result of evaporation?
<Mmm, over how much time how many inches of water? And then it virtually stops? It's the skimmer...>
Any help you could provide would be most sincerely appreciated. Thank you.
Richard Agins
<Please send along a link to the actual product if you can... and I will do my best to help you. Bob Fenner>

Re: Pond question, through-put/skimmer leak  - 8/17/07
Here is the link to the skimmer - I have the small (which isn't all that small): http://www.justliners.com/easyproskimmers.htm
and here is the link to the extension tube: http://www.justliners.com/easyproextentube.htm
<I see... the material the "clamp mechanism's faces" are made of is some sort of plastic... likely PVC sheet...>
I didn't mention that I installed the extension tube to the skimmer using a double bead of silicone.
<This is what I would have done as well... a few "squigglies"/lines on either side, waiting ten minutes or so...>
Both the skimmer and the extension are made of a resin or polymer of some sort, are rigid, and bolted together quite tightly.
<No need to be "too" tight>
In response to your question, 2-3 inch drop in water level in 2 days with the pump running. I can't imagine that there isn't a reliable way to make the skimmer connection without leaks. This has taken more time than any other aspect of the construction.
Thanks again. Richard
<And you've tried leaving the system w/o the pump running with the same water loss I take it... 2-3 inches in two days is a bit much... unless there is a good deal of splash, spray involved... and or very dry/high winds... Myself, I would try taking this all apart (yes, once again) and re-Siliconing both faces... and let set up for a day w/ the water low to let set. Bob Fenner>

Re: Pond question - 8/17/07
Thank you. I left the pump off today. I'll review the situation when I get home tonight to see whether there's been a further drop. Your advise is much appreciated.
<Real good. BobF>

Question regarding pond liner and UV exposure.  6/9/07
Hi Crew,
I tried to find the answers to my queries all over the net and I couldn't find a good answer.
<May not be such...>
Therefore, I'm writing you to get an expert advice. I just built a 1800 Gal. pond (approximately) with underlayment and liner.
<What sort of liner? Material, thickness?>
The pond is 28" deep at the maximum and 14' x 7' in length and breadth respectively. I have covered the edge of the pond with stones ,as such , the liners aren't exposed to the sun in any way. I was thinking about covering the bottom of the pond with stones or gravel but according to many experts on-line, this is not a good idea as the debris gets trapped in the gravel or rock and creates an anaerobic condition .
<I agree>
My question is; would the liner be safe at the bottom of the pond underneath the water?
<Safe from?>
Some website say that UV rays won't penetrate down beyond 1.5 mm inside the water. When I did the research about UV rays, I found out they can penetrate well up to 15-20 feet deep in water. What do you think i should do to keep the liners safe from UV rays and maintain a healthy pond?
<Ultraviolet is not an issue here... but some types of liners (Polyethylene) degrade over time w/o such exposure... and all liners are subject to puncture... with rock, roots, shoes... See WWM re the use of reinforcing mesh, concrete OVER such liners. Bob Fenner>

Re: PVC pipe cement to adhere patching material, not reading...  5/31/07
Wow, thanks for the quick response. I say the liner is PVC, because I described it (black on one side and green on the other side - like flattened out garden hose) to a local landscape/pond company and they thought it was PVC.
<...>
Does the that description sound to you like PVC. I did try a test, and other than a little shrinkage, it seemed to work OK. I'll check (bench tested) it again at 24hrs post application.
What kind of waiting time to refill would you recommend.
Thanks again for your timely response.
<Please read here: http://www.wetwebmedia.com/PondSubWebIndex/linerpdrepfaqs.htm
, and the linked files above where you lead yourself. BobF>

Pond <repair> Question    5/11/07
I have a 7000 +/-gallon pond with a waterfall and coping around the rest of the area. This has been set up for about 5 years and from a biological POV has been very successful. The problem we are having is the coping stones are tipping into the pond. Although they are set in mortar and grouted in between  they are no longer stable.
<Mmm, wondering what became of the mortar base>
I have spoken to my mason who helped me build the pond and he said we could pin them in but we have a EPDM liner. Do you have any suggestions to lock them into place.
   Thank you for any advice you might be able to offer.
   Michael Jove
<I would lower the water level, remove the present work and lay in a new mortar (actually I'd use concrete and reinforcing mesh... chicken wire or stucco wire... that you can cut with shears... let this set up for a day, and mortar the coping stones with mortar the next day (maybe with a bit of lime or white glue (the mason will know what I'm referring to...) to make all a bit "stickier". Bob Fenner>

Re: Pond Question    5/11/07
Thank you for responding so quickly.< I wish all consult/repair services were so timely>. The mortar base is still there but because it is set on the liner which has give I am sure that shortened its lifespan. Your suggestion of either lath or a rebar equivalent is something we have been mulling over and now will probably use.   
  Thank you once again.
<Welcome... I have done such repairs before... If the present mortar is substantially adhered to the liner, I would just leave it there, remove the coping stones, re-sent in a new foundation built over the present stuck-on mortar bed. Bob Fenner>

Lifting boulders out of pond to patch flexible liner  - 03/24/07
Hi there,
  I am hoping you can help me figure out what I need to do to levitate a big boulder so that the flexible pond liner underneath can be repaired.  (The aftermath of a shady contractor.)   I have thought about using an engine hoist, but they are designed to be used on a level surface and would not straddle the distance needed to be on the stable banks about 6-8 feet wide.  I have thought about a installing a boat hoist outside the pond, as well.  I have also thought about (simply) rolling it out of the pond and banishing it to the status of land-based rock feature outside the paradisal pond.
  What think ye?
Thanks,
Jody
<Mmm, first and foremost to make cautionary remarks re smashed body parts... Remember thou art mortal! Secondly to state that any movement of this rock, smooth or not, may well tear your liner... So... Do get, place "carpet remnants" or samples about one edge/side... and with lots of coordinated, strong friends... with good backs... lift... with your legs... the rock onto the aforementioned carpet... and scoot more of the same under the edge just lifted... go over to the other side... lift and scoot the carpet pieces further in... Am hopeful this rock is not too large/heavy to allow this prep. work... IF there is sufficient stability, AND room around the edges of this water feature... you may be able to "chain" this rock (securely... with bolts, washers, nuts twixt overlaying links... Tie all this to some sturdy lumber of sufficient length to straddle the pond... re-locate those friends we listed before... and brute-strength, lift this rock out... more carpet pieces laid out in the direction the rock will cover is recommended... DO be careful... and please write back if this rock is too "round", heavy... there are other possibilities. Bob Fenner>

Re: lifting boulders out of pond to patch flexible liner  - 03/25/07
Hi Kind Crew,
Thanks for the prompt reply and the caveat about the squish-crunch factor (ah, the endoskeleton!)
<And meso and exo...>
  The good news is that there's plenty of room around this flat-ish boulder which is sitting on a @ 10-inch high 'pedestal' of stacked pieces of recycled concrete although it is about 4 inches below the level of the bank.  Would it be feasible to place beefy timbers at sufficient width on both sides of the boulder (with liner gathered up like skirts so timber guides rest on dirt) and slowly, carefully.... many chains, bolts, overlaying links strong backs and many tamales later...
<Don't forget promise of cold brewskis later...>
have the damn thing out of the pond never to return again?
<Yes... Do bear in mind... a useful "rule of thumb" that the rock likely weighs about 200 pounds per cubic foot... and do "loosen" it from its perch... likely with a crow-bar or two... or metal pry bars, digging "sticks"... ahead of attempted lifting>
  I could also gather the skirts pad with carpet, pack dirt around the boulder, in effect drawing the shoreline closer, and roll the thing over and over and away.
Given the thus exposed loosey goosey liner (all rocks, plants, water removed,) I would plan to install many layers of liner to prevent further episodes.
<One good one should do it... Tetra's 32 mil... or a nice, thick EPDM/Butyl...>
The contractor used an old rubber-backed rug as cushion on the upper part of the pond, but none
beneath this section of the pond which houses the mammoth rock, doh!
<Indeed>
Nothing like experiential learning, ahem!
<Mmm, I'll cut the first-hand experience here m'self>
  What are the other options?  This is about a 1-ton rock,
<Oh.... really too big... heavy... see below>
originally placed with a back hoe...
<Can you get one of these back there? W/o too much damage?>
The distance from one side of the pond to the other where there is stable ground is about 14 feet, larger than I would've eyeballed it to be.  So 14 feet is the distance any contraption would have to span in order to levitate the rock.
<... ohhhh>
  So the challenge is to lift it about 6 inches, let's say, and potentially move it about 6 feet to the bank and possibly leave it out permanently.
<Mmm, yes>
It could look just as pretty at the edge of the pond.
  When this rock is no longer there and there is in effect a swimming hole in the pond, do you think that having a layer of rocks, sand and gravel on the bottom would pose a great friction problem should a certain pond-wader find her way into the water when it is 112 thousand degrees outside in summer here in Pasadena, CA?
-Jody
<I would "cushion" the entire bottom where the liner will rest... Actually, having been involved in a couple hundred such installs... let me "cut to the proverbial chase" here and state that I would definitely NOT make this just a liner pond... but use the liner (as we used to) as the underlayment... Later on this... The rock I would actually "bury"... too big, much trouble to move... not likely easy to break up in place... I would dig a hole near it... and roll it over, in essence, bury the thing under the future pond... And make the pond as detailed here:
http://www.wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
The second tray... Concrete and Liner Pond Construction... Read and heed. Bob Fenner>

Re: lifting boulders out of pond to patch flexible liner  03/25/07
Hi Bob,
Thanks for the link to the website.  Well, the rock, though 3 feet across, 4 feet wide, and about 18 inches high, must not be a ton b/c it's now sitting pretty on the bank of the pond.  (Two crow bars and three strong backs later.)
<Very strong...>
  I will purchase the underliner and cushion the liner with a double layer of the underliner fabric.  Is it necessary to have more cushion, such as sand, given that the dirt beneath is FREE of roots, gravel, and other disturbing bits?
<Mmm, no... good insurance though... as is staying out of the pond yourself>
  And.. I will simply not use the pond to wade in, and that's that.
<Heeeee!>
Thanks so much for being available and sharing your hard-earned pond wisdom with me!
-Jody
p.s. I will read again your section on container ponds b/c I have a couple of barrels with black plastic liners (like stock tanks) that I could
aqua-fy to good effect.
<Ah, good. BobF>

Pond Liner Lifts   2/20/07
Good Day,
<And to you>
I have searched through your great site and, unfortunately, have been unable to find any information pertaining to our problem.  Our outdoor pond is 8' x 11".  It is 3' deep at one end, 2' at the other.  The pond has a liner.  During our rainy season ground water seeps under the pond and lifts the liner so a lot of pond water drains away.
<Yikes... really need to make a drain away from this "underneath" area... to even lower ground... rely on gravity is best... a pump with a float switch if need be>
When the ground water dissipates, the liner drops and the pond needs to have water added.  This has been a problem since we purchased our house ten years ago.  The liner now has holes
<Yikes...>
and we need to install a new liner ASAP as we have loads of fish temporarily housed in an upper pond which is too small for the long-term.
We are currently working on replacing the liner but we can't seem to get the area to dry out.  We have the pond drained in the afternoon and then next morning there is a foot or more of water in the deep end.
<Yes... same sort of situation, challenge as above... need to either have a purposeful drain, or set up an automated (electrical) pump/switch...>
With the water constantly coming in, we are not sure if we can install the new liner and achieve a good close fit.
<Not likely, no...>
  Do you have any ideas or suggestions how we can properly install a liner and/or resolve our lifting liner problem?  (We live near the ocean and there are numerous underground streams making their way from the mountains to the ocean.)
<Ah, yes...>
Thank you kindly for you time and any assistance you can offer.
Margaret Maringgele
<Mmm, if you had a small pump, you might be able to "sink" this into the ground next to the existing hole (digging), place the pump in a plastic bucket... and allow it to pump out the water while installing the new liner... but really the only permanent fix is the drain or automated pump/switch mentioned. Bob Fenner>

Re: Pond Liner Lifts   2/20/07
Bob,
<Margaret>
Thank you so much for your quick response and possible solutions.  My proposed solution, involving dump trucks and fill, wasn't well received by my husband.
<Yikes!>
Hopefully he'll like your ideas better and we'll have a liner that stays on the bottom of the pond.
<I hope so!>
Margaret
<BobF>

Sealing EPDM liner to cement... possible, but messy  2/19/07
Hi, Bob
<Eric>
I am redirecting an existing waterfall through a narrow gap between two very large hard to move boulders into a new creek, so I need to link between two sections of EPDM with concrete between them (concrete to serve as "pond liner" within the narrow 3"-4" gap between boulders and extend several inches out in both directions. I do not want liner to be visible in gap between boulders. Can I bond the liner to the smooth cement with asphalt emulsion UNDER the water level?
<Mmm... possibly... a real mess though... wear your absolutely worst clothes... very long, up to the elbow and beyond... "ladies" dishwashing gloves or similar for chemical handling...>
If  not, what's the best adhesive?
<This really is (amongst what is widely available) the best material... there are a few formulations... You want the very "viscous" material... likely labeled for roof patching...>
Or alternatively, if I were able to dress the EPDM thru the crack between the boulders, how can I seal it to the rock BELOW the water line?
<A VERY good idea to do this at the "low water level" time of the year... BEST by far to divert or dam the water for a day...>
Asphalt emulsion , construction adhesive calk, RTV calk, polyester resin???
<Only the first will work IMO>
If I go the cement route, is there risk the bond between cement liner and the boulders will crack from settling or whatever creating a leak?
<Always, yes... best to fit this with large, well-shaped rock... and fill the gap (best to actually make a "form" first, and build to fit closely OUTSIDE the system), with a very fast settling cementacious product like Thoro's "Water Plug"...>
Perhaps I should cast in a 1/2" gap between the concrete and boulders on each side and calk it with flexible sealant like that used on swimming pool decks?
<Bingo! A wise choice>
Thanks,
Eric
<Welcome, Bob Fenner>

Re: sealing EPDM liner to cement   2/20/07
Bob, thank you very much for the invaluable advice. Amateur on this end.
Regards,
Eric
<We are all amateurs at all things at one time... Welcome! BobF>

Pond Liner
I'm just starting my outdoor pond.  The pond is built on cement floor and surrounded by cinder block wall as an extension of my planters.  What adhesive can I use to adhere the liner to the cinder block walls?
<Mmm... would be best to "capture" the loose edge under a cap if still possible... mortared over the edge with plastic cement, thin-set and Acrylmix... If you can't do this, please write back and we'll talk. BobF, leaving Houston>

What type of liner to use   7/24/06
Hi Bob,
<Craig>
I'm getting ready to dig a hole and I am a little confused with the different synthetics that go into the liners. Some background.  My 4000
gallon pond needs a liner.  Which of the liner material would you recommend - EPDM, PVC and HPDE/LPDE?
Thank you,
Craig
<Mmm, here: http://wetwebmedia.com/PondSubWebIndex/linerspdconst.htm
and the linked files at top. My preference (by L'Oreal?) is in the order you present these. Bob Fenner>

Will blocks cut the pond liner  5/29/06
Bob,
We are building a pond using blocks.  The pond is 15 x 25.  Will the top of the blocks cut the liner over time? We will be using 42 mil liner then "topping" it with flag stone.  Thanks.
<You should be fine here... this sort and thickness of liner is VERY tough... I would first lay-in the liner (w/o mortar), fill the pond, place the flagstone... allow all to sit for a few days... see if this is about what you're looking for... remove the flagstone, trim the liner where it is overlapping over the outside of the flagstone... and re-place, mortar it in place... with or without reinforcing mesh (Leaving the cap non-mortared is too likely to lead to pieces falling in, this potentially puncturing the liner. Bob Fenner>

Sealing edges of rubber liner fix  12/21/05
Hi,
  I live in NC and purchased 10 beautiful acres with a 50 year old, 1 acre pond on it. It is filled with runoff water. When It rains it fills up nicely , then after a few days the water level drops about 2-3 feet. I see where the water drains out on the backside of the 20 ft. wide dam. Large trees sat on top of the dam and spillway which I recently cut down. I do know the reason for the leaking is the large caverns these roots have caused. I can't afford to redo the whole pond and a farmer suggested laying a piece of 10' X 100' rubber liner across the dam area and down below the surface a few feet to stop leakage or cover holes. My question is, once I put this down and secure it with rocks here and there, won't water just seep under it around the edges and the leaking will continue just as bad as before?
<Likely so, yes>
Do you think this might slow it down to a natural leakage pace?
<Doubtful...>
By the way I do know cutting down the large trees will cause the roots to die and make more ways for water to escape, but the amount of leaves falling into the pond each year is tremendous and trees and root systems were hanging out over pond ready to one day fall in. I'm sure the leakage and/or holes is below the root balls sticking out. Please help, the few fish remaining need some deeper water to survive.
Becky
<Mmm, I suggest you "let your fingers do the walking"... have some local contractors (likely to be found under "landscaping" in the Yellow Page Directory)... and have them tell you your options. Maybe a clay-based material can be dished into your "over-burden" (the unconsolidated material on the pond bottom), or this overlain over the base of the liner on the dam... Bob Fenner> sp;

Pond Liner attaching to existing concrete block wall   11/12/2005
Bob,
First, I'm a big fan of your books. Even though I've never meet you I've heard a lot about you when I used to work at Octopus's Garden.
<Ahh, and Ron now has a much larger, very nice outlet... on Convoy>
I have been in the Reef Tank Hobby for 4 years now and have a nice setup that is thriving because I followed your advice found in your books.  I am now putting in a 3000 gallon pond in my backyard. The hole is dug
<The hardest part...>
and the liner has been shipped. The problem I have is that the liner has to attach to a the cement block wall of my garage. What method would you suggest I attach it to the wall with. I plan on attaching that side first and leaving the rest able to adjust and settle when I start to fill the pond.
Thanks,
Dave MacLeod
<A bit messy, but the simplest means here is to "glue" the liner to the block wall face (well above the water line) with asphalt emulsion... don't wear your good clothes... do wear gloves and have rags, gasoline to clean up handy... Alternatively, much more liner can be sacrificed by having this go up above the block wall and a cap placed over it, on top... and the facing of the wall, liner, concealed in some way. Cheers, Bob Fenner> 
 

Have you heard of a powdered pond liner 8/17/05
I would like to know what this product is and how to use it. If you have any information on it. I would appreciate it.
Thanks,
Sylvia
<Mmm, there are materials like powdered lime, clays that are sometimes (though less frequently as time goes by) turned into existing soil to make a water-proof or more water-proof barrier... What is the application here? Something very large? Bob Fenner>

Re: Have you heard of a powdered pond liner 8/20/05
This stuff looks like sugar granules. You just put it in the pond and circulate the water. And it stops the leaks. I put it in the pond today and the water looks like syrup. I sure hope it settles.
Sylvia
<Yikes, I sure hope you read the instructions, precautions. Bob Fenner>

Leaking 25ml polyethylene liner 8/17/05
Hi crew,
I've had a leaking pond for 7 years. It is made of 25 ml polyethylene and I know where the leak is at. I have tried to clean it very carefully and re-tape it with 6" tape from the company I bought the liner from several times. The tape has worked great except for one place. It is on the north side of the pond and it almost never dries out. What type of solvent is best for cleaning the liner to prepare it for tape?
<... alcohols are about the safest, most thorough...>
I have been using rubbing  alcohol, since it dries so fast, but I'm thinking there must be some type of solvent that is
specifically suited for polyethylene. Also since the area that has to be re-taped has many curves and 25 ml  polyethylene is so rigid is there a better material that can be used to go over the polyethylene, but will stick to it.
<Not as far as I'm aware>
My pond is approximately 120'x30'x9'deep. Replacing the entire liner is out of the question, it has a  shelf all the way around it with rock placed in the shelf and a rock walkway all around the top of the pond. I have spent literally hundreds of hours of my time getting it to this point.  The repair has to be made in place. If you can give me some suggestions I would greatly appreciate it. Dynamite is my next option. HELP
Thanks in advance
Tim
<I wish I had better news for you, but there is nothing that I'm aware of that will help, or repair a polyethylene liner... One of the reasons I am so opposed to their use in biological ponds, basins. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/linerspdconst.htm
Bob Fenner>

Re: leaking 25ml polyethylene liner 8/17/05
That sure made my day, your site is a great source of info. thanks
<Am very sorry for your troubles... we replaced many "poly" liners over the years... no fun, to put it mildly. Cheers, Bob Fenner>

Lessons in liner differences... some are toxic to pond life 8/5/05
We are new to the Koi Hobby, and just built our 1st pond in May,  we have had 7 fish since July, but developed a slice our current liner, so we had men come out and put in a new PVC Blue liner,
<Is this a swimming pool product? Some are treated with chemicals that are undesirable for biological systems>
We moved the fish to a large horse tank  for 3 weeks, while we went bigger and deeper with the pond. we went to our first Koi Pond tour, and got new info and designs.
<Ahh! An "eye-opener"... which invariably folks wish they'd done before setting up...>
Needless to say, they finished installing the new liner on Sat, July 30, and we got the filters going,  the water was clear on Tuesday night, and water test are good, so the fish were transferred back to the pond. We came out on Wed night and the small fish were dead,  The large one was still doing ok, swimming around. We took the water in for testing on Wed night, and all the water tests are normal.  I questioned the oxygen,  it is a 1800 gal pond.
But that came within limit, he indicated that bigger fish would have died first if not enough oxygen.
<This is so>
The water filters completely 2 times a hour with the pumps/filters.  Today the large Koi is dead.  The pond people said that maybe the liner is toxic,
<Yes>
How can we Tell,    the liner people said it is
non toxic.  
<Non toxic to what? Swimming humans... you can "do a bioassay" with water taken from the exposed liner, or soak a piece of the liner in water that you know otherwise to be okay... or ask to see the manufacturer's information re this liner... or take the liner to a QA lab...>
We have well water,  have added  nothing except Koi Clay.  He gave us black crystals to put in a hose and put in the outlet water, to capture any toxins.
<...?>
Help!!   My husband is terribly upset as are the children.  If it is the liner, how can we fix it??
<Can either wait, see if time going by, perhaps chemical filtration will remove... plasticizers, anti-mildew/algal material... or remove, or place a non-toxic liner over this in turn...>
   If it is the liner, can it be treated, so we do not have to tear it out,  does it wear off?
<Likely the latter does occur... but how long...? Bob Fenner>
Carolyn

Lake liner 7/9/05
Hi-
<Hello there>
I stumbled upon your great site and I’m hoping you can help me out.  My boss is planning to build a rather large lake on his mountain side property here in Ojai.  The lake dimensions are 200’x100’x150’ and we’re trying to determine the best type of liner to use.  The soil in the mountainside is rather impermeable…we’ve had difficulty passing perc tests because the ground is so hard.  Our contractor and ranch foreman recommend using a 30 mil PVC liner, but my boss is hell-bent on using a clay liner.
<Mmm, I'm much more inclined to go with the PVC>
  How much would a clay liner run on a lake this size?
<... depends on the make-up of the current basin bottom... a mix of material has to be dished in... Likely cheaper by far than the PVC>
Is it even worth using?
<Yes...>
  He’s talked about bentonite and gunite.  Thanks for your input!
<Not the latter... very expensive. I would have a few of the "lake consulting" and construction firms come out, bid this job. Bob Fenner>
Emily Warmann

Repairing a pond liner, literacy
HI,
   We have a pond in our back yard that has a rubber like stiff liner. And it has a leak. Is there anything I can use to repair it.     thank you  Marty Soloman
<Please see WWM re... the Pond Subweb... Liners... Depends on the make-up of the material, the nature of the tear... Bob Fenner>

Concrete block pond construction
I have read with great interest (and thanks) your section on building a pond with concrete block. The walls will be concrete block and I am going to use an EPDM liner. How does one attach the liner to the block under the coping?
<Basically, liner is underlain twixt the topmost course of block and whatever you're using as a cap (likely more cementatious material or rock, mortared in place. A good technique is to slowly fill the pond without this cap, pulling the liner in place to flatten out, leaving it almost all the way filled to assure a good fit while applying the cap. Bob Fenner>

Custom-shaped pond liner
Do you know of any companies that make custom shaped pond liners?
<Yes>
I am building a 600g indoor water feature (for Koi) in my new office.  It is oddly shaped and five-sided, about 3 ft deep, and I was wondering if I could get a 3 dimensional pond liner custom made to fit it rather than face the creases caused excess liner?
Thanks very much...
Jeff
<Umm, the companies that fabricate liners consider this size piece a scrap... You are best off buying a small liner (I really like the Tetra product for consumers making liner-only systems), and folding, cutting it to fit... these do come in a few sizes. Maybe see Tetra's site re. Bob Fenner>

Pond liner in tank
Situation:
Excellent site with good faq's but mine is a bit specific...
Built a plywood tank and used pond liner (instead of epoxy), and sealed it up with GE 1200 Silicone.  (I got it from a tank builder so I assume its aquaria safe).  
<Is, but doesn't adhere well to liners>
I just poured RO water and after 2 days the water started clouding a bit.  Is this a result of the silicone?
<Nope>
Is this normal and will running the water through carbon clear it up?
<Is normal, carbon will help... but really the "system" needs to cycle... this takes a few weeks... can be sped up... a "break-in" biological period.>
Right now the water is just standing with no movement.
<Better to recirculate it>
Or, is the EPDM pond liner giving something off.... I assume the liner is safe to use for fish seeing as they use it for ponds....  Do I need to prepare it before use?
Please help!
Thanks
Lee
<EPDM is very safe... Please read on WetWebMedia.com re cycling of aquariums... the same series of events occur in all aquatic environments. Bob Fenner>

Seaweed ponds
Hi.
<Hello there>
We have built 2 (50 x 20 metre) ponds for a trial in seaweed production, using saline groundwater.  At present the ponds are not lined, but I feel that they are leaking and could cause environmental problems.  As our local black plastic (polythene) comes in 50 x 4 metre rolls we will have to join 5 large sheets together.  How would you suggest this could be done?  Maybe they could be heated together!!
<No my friend. Our companies (among other ornamental aquatics work) designed, installed and maintained large water features, including seaming nominal 20 mil PVC... we also bought and installed Butyl Rubber, EPDM and other liner materials as underlayments... but never Polyethylene... even the types that are treated to resist "aging" and sun are disappointing... too short effective time spans, too easily punctured... and NO (unless technology has changed...) means of welding (sonic, solvents, heat...) sheets together. The only good things about Polyethylene is that it's cheap and readily available. I encourage you to look into other liner materials. Bob Fenner>
Thanks
Charlie Gillingham
Lake Charm
Victoria
Australia

Question on toxicity of pond liner repair
I have a question. I have a 100 gallon pond set up in my remodeled  attic with some of the smaller fish I bring in for the winter from my  outdoor pond. I had to fix a minor hole near the top of the plastic liner.  I was wondering if the epoxy glue that I used can affect my fish in any  way. Thank you for your time.  
Len
<Should be fine, non-toxic once the epoxy is set-up/cured. Bob Fenner>

Pond Liner
Mr. Fenner,
<John>
How about 36 mil polypropylene for a pond liner? This product is manufactured by Bend Tarp and Liner, Inc. as a liner for holding ponds, etc. They will cut custom dimensions will should be a plus because of the layout my pond will have. I won't have to make any seams. It's also cheaper than many products I've found.
Thanks,
John Jordan
<I like PVC, EPDM, Butyl Rubber... more for their stretchability and resistance to puncture myself. Most any waterproof material will do however, if used under a shell of wire-reinforced concrete... the best available, most-appropriate technology in most applications. Bob Fenner>

Swimming pond 7/28/04
I have a large area where I would like to put a pond.  It has a natural spring that will feed into it via a stream I built with 20 mil liner.  I would like to swim in it.  What liner options would work?  Would I need more sand?  The size of it would be about15ftx20ft. Thank you for your help. Alysia, Asp 
<The same (likely polyvinyl) 20 mil liner would likely work. Other choices available include Butyl Rubber and EPDM (these are generally more expensive though)... A few concerns to voice: Depending on what the ground is like (sharp rocks, roots, invasive plants about...) you might want to "jump ahead" and plan on either shotcreting (over wire) the basin or at least the "bench" (edge)... if not going the gunite route. Do have your water checked (unfortunately) for possible human disease issues due to the source... and lastly, do make provision to prevent vector problems (stock with mosquito fish...). Bob Fenner>

Pond with a view
Hello there, you have been so helpful with my marine problems; I can't help share my pond concerns and thank you in advance for your wisdom. I'm in the design phase of a pond approximately 5000 gallons that will have a viewing panel in the adjacent attached sunk in patio. My question is - how the heck to you get a good seal on an acrylic view port that will be about 2' high and 3' wide? Is Acrylic even the best material for outdoors without direct sunlight? We are in Tucson and are hoping to go with a cichlid pond as opposed to the Koi pond which is why we so desire a side view into the pond.
Thank you for your time. Bill Roh
<I've done this a few times years past. Best to have a "race" frame built, pinch/fit your liner into this and nestle the viewing panel into the frame with silicone. Bob Fenner>

Re: Question regarding pond liners
Thank you for your recommendations, I'll look at the postings for shotcrete. Since I've written to you, we've interviewed a contractor who suggested troweling a concrete underlayment under the rubber liner to deter gophers. She is having to replace her mother's pond for that very reason (gophers).
<Not under, but over... please read through the WetWebMedia.com site re pond construction en toto, particularly with liners>
The screen-wire mesh underneath the liner was to deter gophers from chewing from below, but I don't think it would last long before deterioration.
Thanks,
Linda
<Bob Fenner>
>Question regarding pond liners
>Dear Sir:
>I found your address on the WWM site, I hope you're the right person to ask the question.
>We live in SE Arizona, and want to build a pond with waterfall feature for birds, and also encourage dragonfly and damselfly larvae. We do not plan on fish other than maybe a few Mosquitofish or similar. The size is about 20x10'. The local pond builders recommend the EPDM rubber liners. We have deer and also gophers. How do the liners stand up to these two mammals? We could possibly have javalinas, although they haven't' been in our yard in a year, they do live in the Huachucas.
><All these mammals can easily puncture a liner of any material with their claws, hooves>
>If a screen-wire mesh is put below the liner, it seems like it would rust out quickly.
><Don't understand what the rationale for this screen is... we built many such ponds using liners (generally 20 mil nominal PVC...) not often but sometimes using an underlayment of carpet... to prevent outright puncturing of the liner during construction, rock placement. Almost invariably we shotcreted over and into a wire mesh >over the liner... I suggest you look into this technology (posted on WetWebMedia.com) and do likewise. Bob Fenner>
>I appreciate your advice.
>Linda Feltner

Vinyl Liner Ponds
I got your email address from the website, WetWebMedia.com. I was hoping you could point me in the right direction for an article I'm working on for Pool & Spa News on How to Install a Vinyl Liner Pond. I am looking for builders to interview who can provide a step-by-step instruction on the construction on a vinyl or rubber liner pond. I have a couple of builders I have spoken to already, but need a few more to round out the story.
<What I know, have written is placed/archived on WetWebMedia.com>
My deadline is quite soon--Tuesday, January 27 at noon--so any assistance you can provide will be helpful.
Thanks very much.
Janice Rhoshalle Littlejohn
<If you have specific questions, send them on to crew@WetWebMedia.com
Bob Fenner>
Janice Littlejohn
Pool & Spa News
www.poolspanews.com

Low cost operating pond pump 750 gal.
Hi!
I'm new in ponds matters, and I'm building a pond of approx. 750 gallons. I need your help.
I need the best cost efficient pump for this size pond and the best liner EPDM or the Tetra Pond Xavan liner?
Thank you for your help.  
<I'd look to the fractional horsepower units offered as "Sequence Pumps" here if you can use their smaller size/s... And the Tetra product is not inexpensive, but is an excellent choice. Bob Fenner>

KOI Pond Construction
Bob,
This is Keith Slinkard , Eric's Father-in-law .
<Hello Keith!>
I have some question about the mods that I am going to make to the design and enlarging my fishes habitat.
1. I purchased Firestone EPDM liner and I am concerned about the wrinkles that I think I will have . I think that I want to shot crete over the EPDM ,but can not find directions as to what to do with the wrinkles prior to applying the crete .
<No worries... on a nice warm day (careful not to lay the liner on your grass!) the material becomes much easier to make folds in then>
2. The size is as follows , 18' long X 8' wide X 2' deep with a 1' X 1' plant ledge around the perimeter. All walls are completely vertical . I think this will add to the wrinkles and make the shot crete application difficult. Should I angle them somewhat ?
<No. Best to try and make as vertical as possible... the wire and shotcrete will conspire to make the walls and corners more sloped... In fact, a good idea to use a lower slump concrete/shotcrete mix... and "lay a bead" on the bottom corner seams in an attempt to "build up" the mass of material... much easier than "pushing up" the material after the concrete truck, applicator is gone>
3. I am going to change to a pond filter to like the one you exhibit in fig.10 of your Aquatic Gardens book on page 10 . With the volume of water that I need to move , do you suggest a dry pump, and if so what size ?  
<Yes, not a submersible, and one with as small an electrical current as you can get by on for the volume (at the head) you're shooting for. Please ask Eric to show you the "Sequence" series pumps... if memory serves they have a nominal 1/5 HP unit that should work nicely on your application>
4. Where do I place the supply line to the filter and how do I install it through the liner material to insure a water tight fitting .
<Mmm, best to run the plumbing "inside" the liner, and up and over the side of the system (a bit tricky to prime the first time but worth it). Water for the intake should come from as far away from the return as practical... and from the bottom as well as a side intake (a foot or so down in the water), these with a valving manifold to isolate one or the other (to vent water occasionally)>
Thank you in advance for your expertise and direction . Keith Slinkard   
<Glad to help. Bob Fenner>

PVC liners
hi--we're not creating a pond (have 2 clay ponds already) but need to use pvc of 20 mm thickness to surround our old house to prevent our major basement leaks.  plan to bury it to a depth of 12" then cover with gravel.  I need a piece(s) 6' x 40' -- where can I find such a creature?  thanks for your help--Lucinda
<Can be done (one of our old business (non-extant) used to fabricate such thickness PVC liners for all sorts of purposes (even roof waterproofing on buildings). I would contact the companies listed on our pond links: http://www.wetwebmedia.com/PondSubWebIndex/pondlinks.htm
(Under manufacturers, etailers... and the clubs if any, in your area that have members that may have bought such size shaped liners). There are "scraps" of about the size you list that can be had, or welded together... so keep checking till you find someone who is really "in the business" or actually does fabrication. Bob Fenner>

Rock-looking pond liner - anyone?
I am looking for a pond liner that looks like rock, not the normal black color.  I saw company was selling them, but I can not re-find its web site.  Do you have any info on such an item?
<My apologies (in lateness as well as failure) - I've searched and searched, and simply cannot find what you're looking for.  Hopefully someone who does will see this and let us know, so we can pass it along to you.  -Sabrina>
Thanks, Dave

Concrete gold fish pond
I have asked this question to everyone I can find that knows any thing about concrete or ponds. Now I found this site so I will try you guys. Here goes : This summer I uncovered an old kidney shaped pond in my yard. It is aprox. 4' wide & 9' long. It now is about 30" deep , but appears it should be 6" to 8" deeper to be above grade. Before it was covered up who knows how many years ago, the top edge was broken off so it could be covered with dirt. The walls are made of a concrete & something mixture with 3" field stone mixed in for filler. The inside walls are nice & smooth, coated with a light gray mortar type material. My question is what is this concrete mixture? It seems years ago I heard that concrete & vermiculite where mixed sometimes to make a lighter & more workable mix. If that's true how do you go about something like this ? Any other advice on a pond of this material would be helpful! Thanks in advance .Steve from Ohio  
<There are a few possibilities as to the mortar mix that you describe, however only one tried and true "re-make" possibility to ensure the watertightness of your refurbished pond. It's detailed here: http://www.wetwebmedia.com/PondSubWebIndex/concrepart.htm
Skip ahead and around to the pieces on liner use/construction. Bob Fenner>

EPDM pond liner return channel...
Good Afternoon,
i would like to install a pond utilizing an EPDM pond liner but have limited room to provide a typical return for the end of the liner.  Does some sort of prefab, return channel system exist or has anyone made one that works well?  If so, what materials did you use, etc. etc.?  Thank you and i look forward to your response.
Regards,
Carol
<... A "return channel" as in a way to run plumbing back sight unseen? You can install a through hull fitting/drain through the liner and attach plumbing to this and remote it where you want. Or do you want to affix a channel as in a stream to your existing basin? This can be accomplished by overlapping a section of liner over the side of the existing basin... or there are other, mainly fiberglass streams, filter boxes that can positioned adjacent to your pond. Some of these are more fully discussed, illustrated on our pond subweb. The index to this is here:
http://www.wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
Bob Fenner>

Re: EPDM pond liner return channel...
Hello Bob,
Thanks for the speedy reply!  It's obvious I'm using the wrong terminology...i need some way to secure the liner without draping and securing the liner over the pool edge.  The pool is rectilinear in shape with vertical concrete pool walls.  i thought there may be some way to fasten an aluminum, u-shaped (?) channel, or some other apparatus, that will hold the pool liner in place above the water level.  The corners are also going to be a nightmare to be sure.  Any suggestions???  Thanks again Bob!
Regards,
Carol
<Oh, I see. Yes, there are ready-made tools and materials for what you want to do. Use your phone directory... and if there is one in your area, under "Swimming Pools" you will hopefully find a company that installs and/or repairs vinyl swimming pool liners. They can show you the "tricks of the trade" here. Bob Fenner>

Re: EPDM pond liner return channel...
Good Morning Bob,
You are a life-saver!  Thanks for the info and support.  I'm sure we'll find
a solution now.
<Glad to be of assistance. Excelsior! Bob Fenner>
Regards,
Carol

Pond fish
dear crew,
    A fantail and a comet goldfish in my pond seem to have white pimple like spots on their gills.  I am unsure at what this is, but i have heard this could be related to spawning. Any ideas?
<This time of the year (Spring, warming) this is very likely the case. There are some pondfish ailments (e.g. fish pox) that can look similar, but highly unlikely here>
When i was visiting Canada recently i saw a huge goldfish that must have been released there.  We almost caught it with our net. I would have loved that fish for my pond.  Also, next year we are upgrading our pond to about 3000 gallons. What type of liner would you recommend?
<The thicker... at least 20 mil, the better... butyl rubber or EPDM, but vinyl will do...>
I am currently using EPDM rubber, but if there is a better type i would like to know about it.
<Oh! This is fine. Bob Fenner>
                                                            thanks
                                                                    Holden

LINERS TO GRANITE???
Apparently, you had some problems with my reply in all caps, sorry about that... I'll try again...
I'd like some further elaboration on the first technique you mentioned, (I.E. "We had some success with either joining the liners to such rockwork on their "front" sides "), as these boulders a far to large to lift. I'd be most interested in materials and techniques/processes (i.e., do you have to grind the granite down to a semi-smooth surface to get a good attachment or have you used some form of thick liquid glue material?
<Good idea to "acid/bleach wash" (notes on WWM re) the rock that is being attached to, and use asphaltous based material (like roofing "lap" cement) to stick the liner to the rock (be careful applying, this stuff is messy). For small jobs, using a chalk line and water level to find, measure the upper reach of the liner, making a mark a few inches/centimeters above this to give you an indication of where the liner is, perhaps using caulking gun sizes of the lap cement to apply a bead of sealant (rather than a open bucket and trowel for larger jobs) right below the lower of the marks.... let the lap cement set-up for a day, trim the excess liner... Bob Fenner>
Thanks,
Shawn

Pond Liner Leak
Hey Crew,
<Howdy>
I have a slow leak (About 100 to 150 gal. a day) in my reinforced woven 40 mil. plastic pond liner. The pond is approximately 4,000 gal. I noticed this problem after we had several days of cold weather in the lower 20 degrees. I am in S. GA. I drained the pond and repaired all the small holes, etc., I could see. I checked the seams from end to end. There are no leaks in the plumbing, UV, bio filter, etc. I still have the problem. Do you have any suggestions?? Is there a sealant I can use? Thanks, Charles
<Unfortunately, there’s no actual sealant that I know of but do check out http://www.wetwebmedia.com/PondSubWebIndex/concrepfaqs.htm as there’s a lot of info on repairing leaky ponds there. Also do a search at www.wetwebmedia.com for pond liner leak or pond liner repair. Ronni>

Pond Liner Bubble
We have a 1 acre pond which was lined with a nice thick liner a while back.
<Nice>
In the past few days however it has developed a 25' diameter bubble in the middle (see attached picture). Any ideas on how to fix the immediate problem and prevent a future recurrence?
<Yikes... I wonder as to the cause... the make-up of the gas itself... Some way needs to be devised to install a vent...like a "sideways drilling" operation... a pipe to the area directly underneath this bubble, water, liner... to allow the gas to escape... Perhaps a well-drilling co. in your area can help... If you had known of the gas problem, perhaps shaping the basin to be more conical would have prevented this condition. Good luck, and do have the gas checked... it could be something flammable. Bob Fenner>
Thanks, Glenn A. Hartzog

Pond shoreline design problem
Hello folks
<Cheers, my friend>
I have been referred to your site by someone who answered one of the posts I have placed on several boards regarding this problem.
<welcome my friend. Do be sure to visit the home page at www.wetwebmedia.com and navigate the links to our many articles and FAQs. This is one of the biggest websites that you will ever see... over 300 megs!>
Before I ask my question I noticed someone with a home made food question, could I refer you to
http://www.easyfishkeeping.com/fishyforum/forums/message.asp?r=forums&t=General&I=1040
I now know about WNV but my fry have more than doubled in size on this diet in the past week. WNV is not a problem in the UK that I know of.
<outstanding... thanks kindly>
Anyway to get to my question or problem.
Back ground first
I have built( finished building last night, just touch ups and this shoreline left) a concrete pond of aprox 2200 UK gal 2600 US gal.
It has three depths, 4', 2', 1' and vertical walls. I will be using a plastic liner, pvc or Dupont Xavan, I can afford butyl.
The pond is above existing ground level by 1' and will have a visible wall on 2 sides, a hedge on the 3rd and a rockery with waterfall on the 4th.
I will 'line ' the concrete with expanded polystyrene sheeting ( Styrofoam, I think ) to protect the liner rather than use underlay.
<indeed, many materials used here... old carpeting, parched clay, rendered sand, layers of newspaper, etc>
BUT
Basic outline of my problem.
I want to cast, in cement or concrete, a ramp on top of the upper coarse of block work to create a semi submerged shoaling shoreline. I intend the ramp to start 2.5" below the water surface and for it to rise to 0.5" above the water surface, gradient 1 in 3. It is to allow animal access/escape to/from the pond.
<very nice>
For the purposes of this post I am concerned only with the construction problems, I have taken into consideration my possible UNWELCOME visitors and here in the UK we don't have the diversity of predators that exist in N. America, I hope the rest of the pond design will keep my fish safe.
<very well>
I see 2 ways of completing my shoreline 1) bring the liner up over the ramp, or 2) bring the liner over the top of the inner leaf of block work and drop it into the air space, then cast the ramp on top of the liner and outer leaf .
I favour the second method, it will be neater and provide a better surface finish. Obviously I will seal the ramp with some thing like G4 or P1 ( common UK sealants ) but I am troubled by the "triple point" where water, liner and ramp meet.
<agreed as I am concerned too. There is also the concern of longevity and repairs/replacement of the liner. The plastic and PVC liners in particular have had issues with longevity and UV stability. The latter method would not be at all forgiving if repair or replacement needs addressed>
How do I seal this properly?
I had thought of 'painting' the sealant across the junction and onto the liner but I have been told that solvents in some solvent based sealants may damage the liner, i.e. G4. 
<agreed>
I can get water based sealant which should be ok, P1.
<yes... but I am still not sold on the practicality of the design inherently>
Other solutions based on idea 2 are 1) In addition to the above run a bead of silicone aquarium sealer around the "triple point" , possibly in a rebate cast into the cement and cut out of the polystyrene <poor adhesion to plastics particularly in temperate zones>
2) Bring the liner up 'behind ' the back of the ramp so that the liner finishes above water level, but this may create neatness issues also it doesn't provide a secure foundation for the shoreline.
<actually I like this solution best thus far>
3) Cast the shore line in sections, seal all of each section and then 'glue' it down onto the liner with silicone aquarium sealer.
<likely very temporary (3-5 years before failure IMO)>
One area I will have to silicon goo is the folds in the liner where they pass over the block work.
Additions resulting from replies to my posts are 1) cast the ramp in waterproof concrete, a simple idea that will help greatly, why didn't I think of it and does away with "3)" above <agree... hydraulic cement was the first thing that crossed my mind above when I read "ramp in water". Quite durable in water>
2) cover the triple point with liner seaming tape.
<also a temporary solution in my opinion and unlikely to even see 5 years of service>
I would be very grateful for your thoughts on my problem and solutions and for any ideas that you have. Thank you Sean McKinney
<I don't know if I've been much help, but I sure have enjoyed hearing about your fascinating pond. With kind regards, Anthony>

Re: pond shoreline design problem
Thanks for your reply to my last email,
<our pleasure>
your point about liner longevity is well noted, the adhesion of silicon goo to plastic hadn't occurred to me, thanks for that, I have just had a trial run at liner installation using 2 sheets of 6m x 4m polythene joined with brown parcel tape to make a single sheet 6m x 8m.
Judging by the folds I have had to included I may well have to bring my liner " up behind the back of the ramp " . Your favored solution. I very much doubt that I could seal all the folds with the silicon goo.
<agreed, my friend... none else seem to be a good 5+ year solution for a liner that is otherwise good for so much longer>
Thanks for your input.
<with kind regards, Anthony Calfo, Wet Web Media>

Leaking Pond Liner
Do you know of any product that can be sprayed or painted onto an existing pvc liner to make it water tight? The liner is only a few years old but it no longer holds water.
<There are no such "miracle cures" as far as I'm aware... but most liners can be repaired pretty easily by solventing (aka "welding") a new piece/sheet of material over the cuts. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/linerspdconst.htm re pond/liner construction... and the links, other files beyond. Is yours a Butyl, PVC, EPDM liner? You will need to know this, and find a compatible/matching material to anneal to it, and solvent to do so. Bob Fenner>
Thanks, Fiona Casarini

Pond Liner for Salt tank set up?
Bob,
First off LOVE THE site!!
Just found it and it's a wealth of info. I have a quick question 4 yaw.
I'm considering making a large salt tank and was wondering if the normal pond liners would be ok for constructing a salt tank used for sharks and rays etc..... If pond liner won't work is there any other material other than the Rubbermaid tanks etc...... I want an indoor pond but with sharks I figured the cheapest way to get a 6x12 tank would be to go pond liner..
Thanks and keep up the good work. and thanks in advance.
<You are welcome. I have built such "shark tanks" (and more) out of pond liners (nominal 20 mil. polyethylene ("water bed") types to 32 mil reinforced, EPDM, Butyl Rubber... with good utility. The large Rubbermaid tm oval "troughs" are also very useful. A note of caution: Do make a complete, secure cover over either, as even apparently sedentary sharks can/will launch themselves out... Bob Fenner>
Regards,
Robert C. Taggett

Pond Advise
Bob, I am assisting a landscape customer with the installation of a water feature just off of her patio. It will be concrete block with a veneer of brick to match the back wall on property line against which the pool will be built. She has about 5 goldfish and prefers no plants. We plan to use an in-line pump with a pressurized filter. A bottom drain will also be installed. Because my client wants an interior color of aqua green, we decided to make the concrete, rectangular structure and line it with a 30 ml aqua turquoise liner. Will we need to treat or paint with a rubber paint the concrete before we install the liner? Thank you for your help, Sally Rudisill, Landscape Designer, Owensboro, KY
<Sally, you will not need to treat the concrete surface, however a padded underlayment is strongly recommended between the concrete and the liner to reduce the likely hood of small tears from the pressure of the occasional foot in the pond, the weight of rooted plants in pots and the very weight of the water itself. Tetra makes a commercial underlayment but many folks use heavy felt to used carpeting just the same. Best regards, Anthony Calfo in your service while Bob travels.>

Pond liner
Please see our website at www.bendtarp.com for information on the nation's best pond liner values. Please contact us if you would like a color brochure with samples.
<Mmm, will post your company name, link on our general, pond links pages, articles on using pond liners... and send your note along to friends/associates in the trade. Bob Fenner, WetWebMedia.com>
Thank you,
Bend Tarp and Liner, Inc.
1-800-280-0712
bendtarp@bendcable.com

PVC liners
Please quote your best price for PVC liners, 20 mills thick, black color.
The application is for irrigation canals.
<Gosh, haven't sold liners for ten years... Please do use your search engines with the terms, "PVC Liner"... Bob Fenner>
Hatem

Repair Question (Liner Pond)
Robert,
This is Doug Carrion. I live in Los Angeles Ca.
About 2 weeks ago I had some trees cut back on my property, only to find that one of the branches while trimming punctured the bottom of our Koi Pond. 
<Yikes>
I had just bought the house, so I am brand new to the world. It looks to me like it is a black liner of some sort. How would I know which material this pond is?
<It may well be printed/embossed on the material itself (if you can pick enough of it up to take a look), or at least the name of the manufacturer... Likely a Tetra product, green on one side, black on the other... 32 mil PVC... EPDM and Butyl Rubber have definite feels, looks to them...>
Also, for repairing, do I take the chance of melting the material if I choose the wrong patch? Well if you could point me in the right direction, I would greatly appreciate the help,
Thanks
Carrion
<Cutting to a/the chase here, do have one/two "pond service companies" come out and bid on this repair... They should be able to detail your possibilities quickly. You can then decide to DIY or no. Not much chance of melting the material if choosing wrong patch technology though. As I say, check through the "Yellow Pages" here. Bob Fenner>