Pond revamp

I built this pond maybe 17years ago, it is block work fibreglassed. About four years ago a fish died without me noticing and made the water go bad which killed all of my koi. My own fault and totally preventable. We'd had some of the fish for over 20years. It has sat since then just stagnating and a perfect home for fly larvae. Its time to make it presentable again.



There is a filter under that lot



I started draining, the smell was grim once things got disturbed



The original pump was seized so I had to siphon the remainder of the water



Id forgot I just chucked all of the jap matting media into the pond

If you've ever mucked pigs out then you can appreciate the smell. I let the sludge drain for a couple of days and bagged up about 10 bags of stinky stuff. Not sure how I'm going to dispose of it. I cant imagine the recycling place will appreciate it. Could maybe dig a hole?

The plan is to add a window into this side, it used to be a nice little nook totally covered with ivy and clematis. It collapsed so had to be trimmed back. I'm also planning some kind of gazebo type thing so there might be some woodwork.





I dug out the old breaker, this thing has been indistructable. I'm sure it was an argos special.



It was slow going, took me 3hrs to do a 1.3m by .6m hole. I've ordered the glass but theres a 10day lead time this time of year.



Whilst tidying around the garden I found some timber that I'd piled up because it may have come in useful. It was the remnants of my old allotment greenhouse. I decided its been sat there for 10years and not been used so started sawing it up for fire wood. After a couple of cuts I thought that looks like decent timber, so I ripped a couple of sides off and its only bloomin cedar. I cant burn that.

I don't envy you one bit.

yesterday I raked loads of sludge and decaying leaves out of our old natural pond, no liners or anything but spent more time releasing the hundreds of newts that came out with it. No wonder few tadpoles survive in there.

Nice save with the wood.

I don't envy you at all - the revamp of my pond will, hopefully , be an easier job to undertake. I've a leak about 6" from the top for the level I want. Thought I'd found and sealed it but definitely haven't. That means I have to put in a new liner - which means removing the 5 Wakin goldfish, 2 tench and goodness knows how many minnows - the only fish that seems to be able to breed successfully... if only a small number fry survive! Not looking forward to netting them out and putting into some large containers with netting over to try to stop the minnows jumping out...

Wish you great success with getting yours up and running again

Looking forward to seeing your progress with this Wallace

I shall watch progress with great interest, Wallace.

If you want ‘smell’ then you need to come round here! LOML commented about the sewage smell in one area of her garden and that the ground was moister than elsewhere. So I dug a shallow hole to see what would happen. Filled with black stinking liquid. Hey ho. The drain man cometh today with camera and shovel.

RogerS said:

I shall watch progress with great interest, Wallace.

If you want ‘smell’ then you need to come round here! LOML commented about the sewage smell in one area of her garden and that the ground was moister than elsewhere. So I dug a shallow hole to see what would happen. Filled with black stinking liquid. Hey ho. The drain man cometh today with camera and shovel.

Click to expand...

My sister lives a few doors down and I noticed that boggy smell, she had raw sewage coming up where the kitchen drain goes into. Covered a decent area. Council maintenance man came with his rods and said nope. The local water authority were called. Stuck his camera in. Apparently he thinks the kid next door had been shoving random things down. The last time it happened next door got a few hundred quid fine for allowing building rubble into the system.

Frank we have another little pond which leaked so I put a butyl liner in, that stuff is really strong

Thanks @wallace . I bought a new liner last year while a sale was on... after trying for ages to find the leak point/points. I could see an area on the brick wall (it's a part raised/part sunken pond) so *thought* I'd be able to resolve it... failed - so replacement liner to go in after some adaptations made with fish plants removed... Just need a spell of decent weather - and no interruptions from family members

That was harder than I thought it would be. Note the catwalk ladder for safe ingress into the pond. I found to my horror that normal ladders dont like fibreglassed areas. Just managed to save myself.



swmbo had a cunning idea, wouldnt it be nice to see the fishys from the house. Theres a window at the tea making area, so I spent a few hours chopping for another window.



We seem to have adopted a black bird. He has a broken beak. The bottom does not move, I think he must of flew into something and snapped it. He came to the garden very tatty but has improved quite a bit. When he wants some food he goes to a window and stares in. I go out fill his bowl and whistle. Seems to have a scruffy robin in tow thats half way through a molt.



He's not too bothered about the dogs either

Good on you for helping your new friend the black bird.

The glass arrived, laminated toughened and weighs a tonne. Well 56kg. The koi hobby is one of those things where as soon as you put the name onto a product the price doubles. Black silicone, probably £6 a tube, koi version £20 a tube



I got the rebate fibreglassed. I have a friend who does grp roofing and asked him for a bit matting and resin. But then I read into the stuff used for ponds and it has to be low styrene stuff, or else it can leach into the water and poison the fishies. Just need to sand it a bit to remove sharp bits then do the flow coat.

I only prepped half the wall for some reason before putting flow coat on, so when that cured I sanded the whole wall.


And then mixed enough to do it






I got the glass installed and went through 7 tubes of fancy stuff. This is my good run of silcone the rest are like dogs hind legs. It is weird stuff, spraying it with water and washing up liquid doesnt help it look good, you have to get your best finish from the nozzle.



I got a scratch coat of render on

I started the first fill, its always good to know how much water it holds just incase you need to medicate.



I rescued all the jap matting, lots of pressure washing, theres probably £200 so worth the effort. It will be getting disinfected later.



The uv lamp was toast, being sat in the bushes for years will do that. Luckily only a new tube and clean is all that it needed.



I filled the pond up and the it holds 10,300lts including the filters. It was quite nerve racking when it came to the windows. I found a leak on the filter chamber so had to re fibre glass around the inlet.

That’s quite a job you’ve done there Wallace, looks really good.
Missed it no doubt but what is the purpose of the Jap matting?

Ian, Japanese matting filters the water (which the Koi poop in obviously) and when mature the matting holds healthy bacteria that conditions and clarifies the water dealing with nitrates and nitrites etc. The lamp kills green algae, which does not harm the fish but makes them hard to see and will collect on the windows and walls. The alternative to Japanese matting (or addition in a separate chamber) is K1 - which are a kind of hollow plastic bead, usually agitated with oxygen pumped into the filter tank (as well as into the pond directly). The water has to be matured by adding fish gradually, so that the filters build up capability over a few weeks. Tested with special test kits to ensure Ph is in a safe range. The water has to be partially changed regularly and residues cleaned out of the filters with conditioned water. Water is usually run through a carbon filter to gas it off before new water goes in the pond.

This method of filtering is an old school one, most modern koi keepers will use K1 as Adrian mentions usually in modern filters called nexus. I did think about changing but the breeders in japan still use this stuff so it cant be that bad.
The big vortex thing behind removes any solids from the water, they fall out of suspension as they travel around. Sometimes filter brushes are used to trap detritus. The jap matting is the main home for the bacterial side of filtration, Ideally you dont want it clogging with poop as it will mess the process up.

We had Jap matting in our first Koi pond at the farm 25 years ago. Multi stage filter quite remote from the Koi pond. Can't recall if we had an air pump. These days as Wallace says, in a different place, we use a Nexus with K1. Keeping Koi if you want show or very large specimens is a bit of a pain actually. We also have Koi fry in what we call "the canal", green tench and sticklebacks etc in the nature pond, and Golden and Blue Orfe which I was told would not breed - but they have multiplied like mad in a much larger and deeper pond that has some flow and is aerated.

When we visited the Koi farms in Japan some years ago, a lot of breeding and growing of the top class Koi was in mud ponds, with active water from mountain run off, and high clay and mineral content. Rather specialised. It was interesting but I am far from obsessed by Koi keeping - it's just a feature of the garden, which has five ponds.

Having a window in the pond is nice. We don't have that so I'm jealous!

I suppose its good that my pond is just a dinky one, the windows are small but look ok. Once you get not much bigger there is a huge step in price. These were £200 each and if you increase the size by just 50cm the price becomes £1000 each.

Just how intelligent the Koi's are.