Sealing a barrel? (Garden water feature mk.II)

Soldato
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Hey all, looking for ideas...

Last year I built a water feature in the garden... (skip this paragraph if you don't care and want to just get to the question). I bought a metal "tree ring" which I sunk into the ground, then filled with stones/pebbles to create a level base, onto which I put a half whiskey barrel. I lined the barrel with a pond liner using tacks around the rim at the top, then stood ~5-6 bricks on-end in the bottom that are supporting a steel mesh, and onto the top of that are some larger pebbles arranged to create a pool. So rather than being a "pond" the depth of the barrel, it's more like a shallow pool (for birds etc). There's a submersible pump in the centre that bubbles up through a stack of rocks in the middle... It works, looks and sounds good, but it's leaking - the barrel isn't watertight in the first place (hence the liner) but my guess is that they liner has a few small tears in it somewhere that are slowly letting water out. Combined with a bit of evaporation and the occasional drops that splash out of the feature from the fountain I'm finding it needs refilling much more regularly than I hoped! (doubly not ideal as tap water leads to more scummy algae etc)

So TL;DR the barrel/pond liner combo I have is leaking (slowly), so I want to drain it, dismantle it, let it dry and try again (the rocks and things need scrubbing anyway)... my question is what can I do to the barrel that will make it watertight rather than relying on a pond liner again which can get ripped or fail?

Things I'm considering:
* Maybe I could get a tube of Dowsil 781 or similar silicone sealer, cut the tip open as finely as possible and then run it up all of the gaps between the barrel slats to try and plug any leaks?
* Some sort of waterproofing paint (like Flex Seal except you can't get it in the UK) - there are various products out there but I'm not sure what would be suitable...

Failing a good solution I could also just replace the barrel with a "sealed barrel" - I found a site that sell barrels with custom made plastic inserts inside to make them watertight, but they're a bit pricey... or with a stone bowl or some other container that is watertight - but I do quite like the barrel and it would be a pain to dispose of so if I can make it work I'd like to!
 
Cut a water butt in half and use that instead?

It would certainly be watertight! But I don't feel like it would look as nice as the whiskey barrel does :p - I think if I'm going to replace it completely it'll likely be with another (sealed) barrel, or with something like a stone bowl or maybe a clay/resin/fibreglass type bowl that looks like one
 

Hmm yeah perhaps this would be okay, I'm nervous about going for another "liner" based approach since my first effort hasn't really worked... but the reviews on this make it sound like it's quite a bit more rigid and durable. The pond liner I bought seemed okay but having fitted it and especially when moving things like bricks, rocks and the sharp edges of the steel mesh I was using it felt like it might not hold up to much - and I guess as I added more rocks to the top something must have torn it in a few places. The barrel actually does hold water, but only up to a certain depth above which some very slight gaps in the slats let water out at a slow rate...

I do wonder though would this really be pliable enough to line the barrel properly? By contrast the line was pretty flexible (like a thin tarp or bit of thick fabric) so it lines the insides, forming folds/pleats that squash right down to the shape of the barrel edges. This seems like it might be too thick for that?
 
It would certainly be watertight! But I don't feel like it would look as nice as the whiskey barrel does :p - I think if I'm going to replace it completely it'll likely be with another (sealed) barrel, or with something like a stone bowl or maybe a clay/resin/fibreglass type bowl that looks like one

I'd obviously misread what you'd done! Thought it was sunk into the ground.

Paint the inside of the barrel with Flexacryl. Maybe even leave the liner in and paint inside that. Alternatively you could fibreglass the inside of the barrel. Bit more effort, but probably cheaper to do.
 
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I'd obviously misread what you'd done! Thought it was sunk into the ground.

Paint the inside of the barrel with Flexacryl. Maybe even leave the liner in and paint inside that. Alternatively you could fibreglass the inside of the barrel. Bit more effort, but probably cheaper to do.

No problem :)

Do you think Flexacryl is non-toxic and safe to use on a garden pond that might come into contact with wildlife? (birds, and I'm sure I've spotted a neighbours cat drink from it at least once or twice)

I didn't think about fibreglass... from memory a mate of mine once built a fibreglass surround for speakers in his car... seemed like you use something as a sort of mold, and kind of paste the fibres on with resin layering it up until it's thick enough, and then normally break it out of the mold - I suppose here I would simple leave it in place within the barrel. That might not be a bad option actually!
 
No problem :)

Do you think Flexacryl is non-toxic and safe to use on a garden pond that might come into contact with wildlife? (birds, and I'm sure I've spotted a neighbours cat drink from it at least once or twice)

I didn't think about fibreglass... from memory a mate of mine once built a fibreglass surround for speakers in his car... seemed like you use something as a sort of mold, and kind of paste the fibres on with resin layering it up until it's thick enough, and then normally break it out of the mold - I suppose here I would simple leave it in place within the barrel. That might not be a bad option actually!

Not sure about it being non toxic. Although it is designed to be used on roofs, so you would expect water run off, so i dont see why it would be.

Fibreglass is very easy to work with, you just have to make sure you use appropriate protection against the fibres (Gloves, mask, etc). As you say, it would be a case of painting the resin directly onto the barrel and applying the fibreglass mat, resin over the top of that and then repeat until you get the coverage and thickness you need.
 
Yeah I was going to suggest fibre glass as well. Often when you get a feature like you mention its got its own liner, just a plastic bucket type thing.

Barrels leak as they require a small amount of water to swell them. As the wood dries out completely it shrinks.

If you want to make a mould then hte way car hifi do it is, fill with a black bin liner (or similar) fill it with spray expanding foam and seal it up, the foam will expand out to fill the space.
When set, pull it out and you have the mold. But its probably easier to line the barrel directly unless you specifically want to make the inner removable
 
In a similar fashion to the above, if you could find a suitable size container for the interior, you could place that inside and then fill the gap/surround with concrete.
 
Great suggestions guys - thanks!

Barrels leak as they require a small amount of water to swell them. As the wood dries out completely it shrinks.

Yeah I read about this, though from what I can tell the more decorative barrels you buy from garden centres etc (like this one) could have been sat for years without being bought and having been cut in half it's possible they might not ever get back to a watertight state... A few people seem to have luck completely submerging the barrel in a big tank of water for several days but that's pretty impractical :p When we very first got it we tried repeatedly filling it with water and soaking it but with no liner the top 1/3 was laughably non-watertight so we gave up!

Could you part fill the barrel with sand and then wedge one of these things in it so it's still barrel on the outside?
In a similar fashion to the above, if you could find a suitable size container for the interior, you could place that inside and then fill the gap/surround with concrete.

That's a neat idea actually! I had thought about using a container inside (especially those flexi type rubbery ones as they'd be easy to trim down if they were too tall) but I didn't think about using something to take up any excess space

+1 Fibreglass it, sealed for life (or until the resin breaks down with UV in about 20 years).

I do think I'm going to go with fibreglass actually - seems like it'll work and it'll be fun! (basically just grown up papier mache!)

My only final thought/question to those that have worked with it before... if I'm just going to do it straight in the barrel (I don't want the cast to be removable, in fact I think having it adhere to the barrel will make the whole thing nice and strong)... is there any danger at all that letting it stick itself to the barrel (as I believe it will do since I'm not going to treat the barrel like you would do with a normal wooden mold) might weaken it (e.g. if the wood swells at all in the summer)? I wouldn't want the fibreglass to crack under the strain or anything like that... (but I think it is slightly flexible anyway isn't it?)
 
Look for gold lable pond seal. You can get it in tubs that you paint.

No need for a liner then and obv no worrys for aquatic life etc as thats what its made for.

I Use the tube version in my reef tank (100% safe or wouldnt use it)

Nice! That's a good option too (although at ~£45 a bucket I think fibreglass beats it out on price at least, depending on how much I would need)... Can't work out if a 1 litre pot of that stuff would be enough
 
Nice! That's a good option too (although at ~£45 a bucket I think fibreglass beats it out on price at least, depending on how much I would need)... Can't work out if a 1 litre pot of that stuff would be enough

Fiberglass Beats on price but will be a nightmare to do i rekon.

Personnaly i would use the gold label stuff if i were in your situation. Will only take a dropped rock to crack the fiberglass somehwere and you
Will be back to square one, it would just bounce off the gold lable, its very similar to rubber
 
Morning all,

Update on the water feature mk.ii... In the end I went with the gold label pond seal paint (so thanks for the recommendations!). Having removed all the existing stuff from the water feature, drained it and removed the liner over the last week or so I let the barrel dry out and then at the weekend hit it up with the pond paint. Gave it one pretty good coat on Saturday morning and then followed it up with a second coat in the afternoon. I'm not convinced that it's sealed the cracks between the slats right the way to the very top (where the gaps were largest) but provided the rest is okay and the water level doesn't have to be to the brim or anything anyway... As of this morning the paint feels like pure rubber, slightly cold and tacky still but fingers crossed it is watertight...

So with that curing for the next week in the garage I turned my attention to the feature itself, I should have taken some pics to post but will try to later or at some point. What we're going for is essentially a bird bath standing in the middle of the barrel with the fountain flowing up through the middle so that the bath overflows back into the barrel. I had been looking at getting something like a stone bird bath or similar and trying to drill it but was nervous about cracking it and so decided to go to the garden centre for inspiration and in the end I was able to MacGuyver a fairly okay looking solution pretty cheaply. For the pedestal/base I took a pair of black tomato pots (plant pots with no bottoms), and stood them base-on-base, and cabled tied them together using a series of small holes drilled near the bottom of each, then drilled several larger holes with a stepping bit in the "bottom" one (to allow water to flow into the middle more easily)...

Then for the top part (the bird bath itself) I got a large saucer thing (the kind that you stand plant pots on for water to pool in)... made a hole in the center into which I screwed a water hose connector by feeding it up from the bottom - the "nut" holding it on is actually an end-cap which I also drilled a hole in for the water to flow through. Then from there the hose can run down and attach to the pump - I haven't decided yet whether I want to put the pump inside the base column or outside with the tube feeding into it, but I'll work that out later. Then we might put some pebbles or small stones in the saucer and it just sits on the top of the pedestal - it feels fairly stable and I expect with the added weight of the water it won't move about (but we'll see)...

Now the agonising wait for this weekend when I can try putting it all together and see if it works!
 
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