Tuesday, 28 February 2012

2000gal pond build

Back in December 2010, i decided to undertake a new pond build, as my previous pond, a sleeper built, 1100gal linerd affair, really wasn't working for me. I had lots of issues with koi health, and thought a new build, done properly this time would cure my problems.
The new build was to be located just a few feet from the house, with a window so i could watch the koi in all weather from the sofa in my lounge. It was also an ideal use for what was a bomb site. This is where it all started:

So, the digging started in January 2011, and it didn't take as long as i thought, bearing in mind the whole build took 3 months. I ended up with a big hole.

I was quite lucky in that i hadn't gone below the water table, so the hole didn't fill with water. Next the aerated drain was set, DPM laid, and concrete pored. 1m3 in total:
The next step was to lay the blocks and facing bricks. The blocks were laid flat, right up to the top at the back/left side, and flat up to the facing bricks on the front/right side, then upright to the top. This gave the facing bricks a nice footing to be laid onto. The window has two lintels, a concrete one on the inner wall, and steel on the outer. Once finished, the sidewall skimmer was set into place.
At this point, things were really taking shape, it was time to get the celotex insulation in, and then have it fiberglassed. This was laid straight onto the celotex insulation, so no need to render the blocks, which saved time and money. The fiberglassing was carried out by one of our club members, John Bulkeley. John has been glassing ponds, making filters etc for a very long time, and it shows, he did a spot on job, very pleased! John also made the window frame, which is fibreglass
Once the fibreglass had cured, the coping stones were laid, window glass set in, and the pond was ready for water! I had also been busy building the steps and wall from sleepers left over from my old pond.
As we have dogs, and to prevent any unwanted swimmers in the pond, i errected a hand rail around the pond. I also put up a pergola, with bronze polycarb to give a bit of shade. Also, a rockery was added to the side to help blend in the mass of bricks and concrete.
Right, filters! i won't lie, i have changed my filter system 4 times in less than a year. I started with a vortex with an easy conversion, followed by a barrel containing aerated K1. I swapped the barrel for a multibay, so i could add Grog after the K1. I then swapped the easy for an Answer 410, which really didn't work for me, flow rates were a big issue, so was the 270w pump running costs. Lastly, after all this, i ditched the lot in favour of a Nexus 200. A much neater unit, easy to clean, and gave me some much needed garage space back. I run 130lt of K1 in the bio side, with 30lt K1 in the mechanical stage. I also heat my pond, using my house combi boiler, via a heat exchanger. the pond and house are both on separate zones, controlled individually, so they don't upset each other. The heat exchanger is run on an Aquamax 4000, which takes clean filtered water from the outlet chamber of the Nexus, and returns into the same. This works very well for me. In the coldest months this year, the boiler was firing up between 3-4 times a day, for just 20min, so a nice cost effective heater. The nexus returns via a superfish 8000, then a TMC 55w UV back to pond. The sidewall skimmer feeds directly into the nexus, via an Aquamax 5500. I have timers on the bottom drain air and skimmer, nice and easy. I will run a Clarity CL3 in the summer to help get the water gin clear.
Im really pleased with the Nexus, it's dealt with my stocking levels with ease. I've been at 18deg for most of the winter. I have 16 koi now, and have had a wonderfull year with no health issues, so what more can i ask for.
And that's it! Until i start the planned extension that is, i'm looking to increase the volume to 3500-4000gal by next spring, just don't tell Sue! Here is a quick drawing of what i'm planning
Thanks for looking, Tim


I had seen this build on, I think, Koi mag forum. Really nice job you've done there! Look forward to seeing if you do the extension!!

Tim we love your massive pond its great, can we all come round to have a look at how deep you go. Have you got any fishy stories for us to hear.

Colin F

p.s. can i join your club?

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