Backyard DIY Ponding Part 1 – I Know What I Did Last Summer.

As we are fully into Fall I am reminiscent of what all I did this summer and a little disappointed in myself that I have not yet finished this project…  I’m not a pond expert in the least, so please make sure you visit some of the sites I have researched if you plan on tackling this project.  It can get quite complicated, but I do believe that with proper research I can learn to do most anything myself.  I know I will eventually get it done – if it ever quits raining.  My pond plan has grown from a humble beginning to one that involves a fully mortared pond with a few koi fish (update: the first picture shows how the pond looks summer 2014 – our koi grew to over a foot in length in a year! You can read more about the update here), an external pump, and a water fall.  All this so we can enjoy our backyard.  🙂  I said I am ambitious, right?
Ironically, my first attempt at a pond in my backyard was not very ambitious.  Honestly, I didn’t know what I needed to do other than dig a hole.  However, many of the steps involved with digging a pre-formed pond are very applicable to digging a larger pond so I will share what I did. This is my first pond: a pre-formed pond from Home Depot…only 40 gallons and impractical for anything other than mosquitoes.

diy pond building

Step One:  Dig a Hole. Yep. That’s it.  The preformed pond was only 16″ deep at most so there wasn’t any need to check for underground plumbing or electrical.  This pond dig can really be compared to digging a hole for a large shrub.  LOL. It helped me to spray paint around the edge of the pond liner so I didn’t dig my hole too large.
diy pond building
Step Two:  Fit your pond liner.  Put it in. Take a look.  Take it out and dig some more.  Finally, put your pond liner in the hole and back fill the dirt around and under the pond edges.  You want the edge of the pond a little bit higher than ground level so that run off water doesn’t end up in your pond.  When you think you have it fitted just right check it for level using either a long board and a level on top of that or a level than reaches from one side to the other of your pond.  If you don’t level it, the water line will be uneven because water seeks it’s own level.
Step Three:  Pack the dirt in as hard as you can.  For a small pond like this you can do it by hand.  Anything larger I wouldn’t recommend.  You don’t want to run the risk of the pond liner cracking over time because it isn’t fully supported.
diy pond building
Step Four:  Use rock to anchor your edges.  This pond is only 40 gallons so it’s hard to avoid the “pond necklace” syndrome.   (A pond necklace is a term the ponders use to describe that unnatural rock circle us beginners often aim for.)  Next, buy a pump that pumps at least twice the volume of water per hour – especially if you are going to have fish.  I bought a 350gph pump from Home Depot and it was only about $30 bucks.  Last, you can add a few small goldfish – assuming you don’t plan to keep them in there for very long.  Even those cheap-o goldfish can grow to about a foot in length.  Adding fish is a complicated issue, but as I progress I will try to make it as simple as possible.
diy pond building
So my pond was pretty complete.  I added some plants and four goldfish (too many I soon learned), but even with my 350 gph pump and filter box my tiny little pond grew nasty in the Texas sun.  The poor little fish almost boiled without daily water changes in June.  So I knew I had to fix this to save the fish!
diy pond building
The next step was to convince my fiancé that we needed a bigger pond.  So, we scooped out the fish and they went to vacation in the aquarium inside. 🙂
diy pond building
We got an EPDM liner from Lowes and expanded the pond from 40 gallons to almost 1000.  I have referenced Nelson’s Water Garden’s website frequently on how to build a pond.  Filtration was the next issue so after some research I settled on the Mini Skippy Design.  Now I do not agree with everything they say about not cleaning the filter and such, but at least, it does provide directions on how to build a decent external filter.
There are several other websites and resources I used to educate myself before building this pond.  I also decided that I wanted the pond to be more structurally sound than just a liner.  Waterbug Design was one website that definitely convinced me that I did not like the look of a liner pond. After reading several articles about mortared rock ponds I knew this was the direction I wanted to go:

diy pond buildingSource: Waterbug Design’s Mortared Rock Pond

Another helpful resource was the Pond Digger’s videos on YouTube.  He usually builds ponds a lot larger than what I was planning, but it helped me understand the process.
Okay, so back to my progress…
We dug bigger hole and this time we referred to our survey to make sure that we wouldn’t hit anything underground.  We were using man-power and shovels so we figured we could stop if we ran into anything suspicious…it’s definitely not as risky as some of those guys using back-hoe’s for enormous sized ponds.  Next, we lined the hole with EDPM liner purchased at Lowes.  This is the thick professional grade liner. Then we held the liner in place temporarily with large stones as we pulled and straightened.  That was exhausting so we called it quits for a couple nights.
I was still hesitant about the mortared rock, but a rainstorm quickly changed my mind.  After a heavy rain I noticed the pond liner had water BEHIND the liner that would not soak into the ground after a week.  I researched this problem in different forums and determined that water behind the liner can continue to cause bubbles under the liner.  Not something I wanted to deal with long term since this can eventually collapse your pond!!
Time to add mortar.  Since my pond is smaller than most I decided to use slightly smaller than head sized stones.  I mortared small sections and waited for them to cure slightly before adding on any more weight when working up the sides.  The mortar doesn’t stick to the liner so you have to be patient and pack it all around the rocks.  My rhythm went something like:  Blob; push in rock; smooth out joints; repeat.  It was time consuming and it took a couple weeks, but definitely worth the stability.  Unfortunately though, it has been raining just enough to keep me from finishing so as of right now it’s only about half way mortared.
diy pond building
At any rate, I will keep you posted and hopefully winter won’t be here before I finish. 🙂
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Backyard DIY Ponding Part 1 – I Know What I Did Last Summer. — 3 Comments

  1. hi, i had built a large pond before using the skippy filter. One key thing when using skippy filter is using the correct filter medium. I would recommend those large floor scrubbing pads they are thick and allow water to flow through and allow beneficial bacteria to colonize in the pad, hence no need to clean as bacteria will eat all green algae thus keeping water clean. when starting up the filter for the first time use Microlift PL to kick off the bacteria growth, sit back and enjoy clear water and happy fish, they work well……the water will initially turn green but leave it and wait 4-6 weeks and you will be amazed as it turns clear as the filter does its job…….good luck.

    • Hi Richard, thanks for your comment. I didn’t use the commercial pads, but I did use something similar that I didn’t have to order online. I also used the beneficial bacteria starter when I first installed the filter- just not the brand you suggested. My research has just led me to believe that the green water is simply a seasonal transition each year, unfortunately. However, it has improved since my last post. Thanks again for taking time to read my post!

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