8 replies to this topic

[27goldfish]

I need help. I think I have the size liner I need, but I want to make sure. I am adding a foot of length and depth. I am also removing part of my shelf. Currently it goes all the way around my pond. At one end, I am adding about 5 feet of width. If I square it off, it will be 10x10x4ft deep. I am thinking a 15x15 liner. Am I too small on my measurements for my liner? BTW, I bought 5 big koi for 40 bucks. All are 6+ inches long. One is about a foot long. Thus, I need to make it bigger!!!!

[Christy]

You have to have a 20 x 20 liner for that size of pond. I was going to put in a 10 x10 by 4ft deep but changed my mind.

[koiguy1969]

yep...a 10'x10'x4' is 18'x18' a 20'x20' will allow 1 ' extra all the way around (thats the minimum,you want)...thats if your measurements are good.

[DrDave]

Just think about how you are going to anchor the edges and margin for error. When you fill a pond, the liner gathers and it does not always leave you what you thought it would.

I personally prefer 18" to 24". I would rather have a little waste then have to buy another liner because I figured too close.

I log the sizes of my leftovers and use them for additional projects. One became my 12' long spillway for my waterfall, fortunatley, I had a leftover big enough so I didn't have to go buy more.

[27goldfish]

I will probably do 20 x 20. Since my landscaping fabric is doing nothing, I may use excess and old liner as landscaping fabric, or do you think that would be a bad idea do to runoff? I have not used any weed treatment in 3 yrs, since I have had my pond. What do you think?

[DrDave]

You do not want any runnoff from rain to enter the pond! You have no control over what is in that water and your fish may suffer or die.

[27goldfish]

that is why I was asking, I am kinda concerned. I can't afford another big fish kill

[DrDave]

You want your pond to have what I call negative horizon all the way around it. It should be enough to prevent torential downpours from causing any water from entering it. So any low areas need to have drains so water cannot pool near the pond then overflow into it.

Edited by DrDave, 13 October 2009 - 10:32 PM.

[D&RW]

Hi there,

Hopefully you have enough storage so you can keep things that you don't use this time, especially odd pipe fittings. When you take apart or put together glued fittings always leave about two inches on either side of pipe. That way you can cut them out and reuse them elsewhere if needed. And try not to obsess about "wasting" money. Like Dr. Dave says, it's far better and less expensive to have an overage of something than to have to start over or reorder.

As for the size of your pond and liner, try to be sure you've actually got 4 ft of depth. Our first pond I dug the deep end to 54 inches for a margin of error. However, with one side of the pond being higher and the way I put in the skimmer I only ended up with 42 inches of actual depth. I used a straight board and a line level that time and it didn't cut it. I'd recommend a tripod based laser level; you can rent one for not too much. I didn't have one until late in this expansion project and I'm still off by 2 in on the one end.

What Dave is calling a negative horizon I believe is what is recommened as building up the sides of your pond so there is a slope away from the pond on all sides.

And for the liner, what Dave says again. You're talking 10 + 4 + 4+ 1 + 1 = 20 ft. That doesn't leave you any wiggle room. If you dig it a bit deeper, say 5 ft = 10 + 5 + 5 + 1.5 + 1.5 = 23. I'd get a 25 X 25 and expand the pond a little if you don't want to waste that much. One thing is for sure, the pond you build is never big enough after it's done.

take care,

Rick,