You've Never Seen a Natural Pool Like This...

I have never seen a pool like it. This is the tale of how an experiment with two tanks and pipes and bubbles in the UK led to the most amazing pool being made in Australia. Four years ago I set up a demonstration on how you can make an organic pool with separate planted and swim zones just with some pipes and bubbles to circulate the water. Following that Justin from Australia approached me for some advice and he went on to make this most fabulous pool. For me this project pushes so many buttons. As well as having a separate planted and swim zone it's made in a hot climate and the whole thing is totally off grid. Justin has had many setbacks including filling the pool with dubious dam water but he's overcome all of these issues and is generously sharing his experience with us. I'll put my original film at the end by way of a reference although it doesn't stand up to Justin's quality. I have learned such a lot from this project and I'm sure like me you will find Justin's film fascinating. Our family really enjoy living off grid so we live on a small acreage near Lake Macquarie which is just north of Sydney, Australia. We were really interested in building an organic pool because it fits into that philosophy. We're very attracted to the idea that the organic pool is very efficient on the electricity and a very good user experience as well like it feels amazing. We've spent many hours going through David's videos and modelled our whole system of his process. It certainly was challenging at times and I lost a lot of sleep over some of the challenges that we faced. We also got a lot of value from other YouTubers and other content creators sharing their ideas and some of the challenges that we encountered I guess we would like to share and give some of the solutions we had to some of our challenges. My number one piece of advice for someone embarking on a project like this is don't make any assumptions. So David is based in the UK working with UK materials, the UK climate, UK flora and fauna. We're in Australia all of those things are different down here and so for that reason it makes sense to try on a small scale and to make sure you really understand what you're working with locally and using the general principles of the organic pool that David has which works very well but making sure you contextualise it to your local environment. The main constraint we had here and the main reason that we actually went for a separate pool or swimming area to planted area is because we were building on a slope so you can sort of see with the continuity of the house and the courtyard we wanted the pool to be on the same level but the ground slopes away so turned out that making it all out of concrete was going to be very expensive so we ultimately installed an off the shelf pool shell and now this is designed to basically be semi in ground this pool shell and it's got struts to support it underneath it's designed specifically for that purpose and it's the same concrete slab that these IBCs are sitting on that. All the plumbing which is experimental in between the IBCs and the pool we can access now so if it didn't work for whatever reason it's not concreted in it's not in the ground it's all accessible underneath this flooring which you see here which can be removed and that was that was key because I didn't know what I'm doing it's all an experiment and so we wanted the plumbing to be accessible in the event that we needed to change the configuration and we did need to change some things so I'm glad that we built it that way. In perspective this pool shell we just bought from a pool supplier in Sydney that was about twenty thousand dollars and these IBCs are basically second hand and they're only ten dollars each and the advantage of those is they've got a frame they're self-supporting sealed as well and so it's quite an economical approach as far as raw materials. At that end of the pool you can see that there are four black their outlets so they're currently turned off in behind there there's four bubble pumps which we'll look at in a moment and that's drawing water from underneath all of these IBCs into that end of the pool and those returns that we can see just here is where the water flows back into the IBCs. We have two skimmer boxes over here to filter the surface debris that goes into the skimmer boxes and then again bubble pumps bring it back around and we also have a David Pagan Butler designed washing machine filter on that side. Here we can sort of get a picture of the plumbing you can see here we've got two key manifolds this is the outer or left hand if you're looking away from the house bank of IBCs and they're running in parallel so this is this is the manifold that comes from the outside end of the pool that returns the water into the top of the IBCs and so you can see these IBCs this is this is a 50 millimeter standoff offset from this main manifold and that's in parallel feeding water from the shallow end of the pool into the top of all of these IBCs what the water will do is it will come back into the top there it will pass down through the IBCs and then come back there into the other end of the pool so the water coming is coming this direction in this manifold and back up into the IBCs and it's coming out of the bottom of the IBCs and going back to the other end of the pool so the water is cycling from one end of the pool to the other end of the pool coming back into the tops of the IBCs and then back out that way the actual layering in here is important it uses the same as David Pagan Butler's system but you have the planted area which is is water and the water level in behind here is just above the bottom of this oh sorry the water level is above the top of that outlet then we have the water then we have sand then we have geofab geotextile fabric and then we have aggregate and in the bottom of the aggregate we have a coil of slotted drain coil which feeds into there and so the water goes down through the biological filter to the geofab and the gravel and then out there the other advantage of using these IBCs we can go around and turn off all of these valves and we can put plugs in here and so we can work on the system independently if there's a problem and we had lots of problems that we had to deal with and it was really handy to be able to isolate all of the IBCs and even some of the IBCs when we were working on them to be able to solve some of those challenges it was also really useful to be able to drain the system and so we had to retrofit them as you can see here but I'd definitely recommend being able to access and drain your manifolds if you're going to go down this path the other advantage to this approach that we have here of having the slab and everything sitting on the slab is that these manifolds which get quite heavy with all of the water in them and are accessible are all sitting on a stable slab while still being accessible as water is being drawn by the bubble pump from the bottom of these IBCs into one end of the pool the water level in the pool rises a little bit and the water level in the IBCs drops a little bit the return water is flowing back in based solely on the height differential of the water between the pool and the IBC so there's no pump returning it it's just relying on gravity another key point here to mention is the diameter of these pipes so you can see we're using 100 millimeter pipe for the manifolds and 50 millimeter pipe for the standoffs the the benefit you get with bubble pumps is that they are very high flow but very low pressure and so I would highly recommend 100 millimeter pipes because even though a traditional pool uses 50 they have these high pressure water pumps forcing water around bubble pumps are not high pressure but they're high flow so you need to use much higher diameter pipes in order to get the flow especially on the return side where it's simply gravity feeding it it's very important to use large diameter pipes so this is our general service bay area for the house and this is the bubble pump that we source from a local septic supplier that is driving the pool and you can see that this is going again into a manifold with four valves these are air pipes that are going through to those four black bubble pump outlets and you can see we've got valves to allow us to control the flow rate of air going into each of those separately so this is a 100 liter a minute 70 watt air pump we inject air at a depth of just about two meters which we'll talk through my calculation is that we are pushing about 30,000 liters an hour of water through the system based on only 80 watts now we live off grid and we have this thing turned on 24 hours a day and the total volume of water in the pool and the IBCs we estimate to be approximately 50 to 60,000 liters of water and based on that we estimate that at a minimum we're cycling the water multiple times per day so not only is it very efficient on electricity it's also extremely quiet and you can't even you can't even hear it the reason that you see here the different settings that we have here is because the outer two are driving the flow rate through all of the IBCs and the middle two are driving through smaller filters on the other side so we actually intentionally use less air in those bubble pumps because we want most of the air and most of the flow associated with the IBC biological filter and less of the flow associated with the drum filter which we'll talk through and that's the reason that these have less less air going through them than the outer ones here we have the bubble pumps there so there's four in total again the outer two are drawing from each of the two rows of IBCs and the inner two relate to the two skimmers and the washing machine filter you can see where the bubble pumps are going there's actually large 250 millimeter or so pipe that goes another probably meter and a half or so down David has some good videos on this in his channel the deeper you can inject the air the greater the flow rate the way that we're injecting air is simply by these pipes but we don't even have any bubble stones on them all we have here is the pipe continues down on this one side and near the bottom of the u but still on this side we have an end cap on the pipe and we have a series of I think they're one millimeter holes and injects air at the bottom of this pipe that air then comes up the pipe and this is sealed here or close enough to seal and so the airflow and the water flow gets drawn out into the pool and we get quite a substantive flow rate from that you'll also notice while we're here we had a problem and this is one of the problems you'll get with these systems with air locks and so what that means is when we drain the water out of it to maintain it or to work on it or to fix things or whatever it might be we end up with an air lock in fact no water was even flowing through based on gravity and we thought that related to the fact that we'd somehow clogged the system up with sand that was getting past the filter or some other problem like that but in the end it turned out there was nothing at all in the pipes we even sent cameras down the pipes and it turns out there was no blockages at all and it was an air lock because we're dealing with low pressure the bubble pumps again I can't underscore this enough you cannot treat them like a normal impeller pump in the system anywhere there's a hump in the system you will get an air lock so you have to put a riser and and I'll also say you can't use the standard air lock release valves from a plumbing department because again they rely on higher pressure definitely the biggest challenge we had was the media that we put inside the IBCs it turns out that aggregate supplies in Australia are certainly in our area and my understanding of other areas is that it's not washed aggregate and the quarries that they come from end up being quite dirty because the use case isn't really for filtration it's for more for civil work and certainly it must be related to the Australian environment such that it's really dirty and nevertheless we washed it we in the truck and elsewhere we spent ages washing the aggregate but nevertheless as soon as we put that in and turned the system on it went just opaque and so much silt you couldn't see it it clogged up the filtration system as well the learning out of that was well what media do we use and and how do we resolve the fact that we now have water in the system that is so dirty and how do we desilt it this pool is such that because it's semi in ground we can't just remove the water from it it needs to have the water in there for the purpose of the structure at least at the bottom level of the pool so we can't just remove the dirty water and secondly we're on tank water here and it's actually very costly to bring in bring in water especially if we want to bring in spring water because we didn't want to put chlorinated tap water into the system nor did we want to wait for enough rain water to fill it so we for all those reasons really wanted to retain the dirty water but clean it up so the question is how do we how do we clean up the really dirty water and how do we or what do we do about the media so firstly as far as cleaning up the dirty water we came across this idea of using a biologically safe flocculant to remove the dirt and the way that flocculant works is that it's designed to take the particles and clump them together and when they clump together they fall to the bottom and the idea being you flocculate all of the material floats to the bottom and then you vacuum the bottom of the pool to remove the sediment it's super important that you understand the role of ph because the flocculant is extremely ph sensitive and we had to dramatically move the ph of the pool in order for the flocculant to work we had to change the dose we were using and the type of flocculant we were using and the third thing is mix the amount you mix in also has a material impact on the flocculation so we ended up doing many hours and many jar tests inside and dosages until we eventually got to the place where it worked once we got the flocculant working we then ultimately used a siphon system to remove all the flocculant out of the pool because one of the advantages of being on the slope is we could use a siphon system and so we used a standard pool vacuum to remove the flocculant from the bottom of the pool to out which meant that we still needed to top up the pool but we didn't need to completely replace all the water in the pool so it took us a long time to figure out how to use that flocculant but ultimately you can see the contrast between the water we have here now which is majority the same as that that dirty water and the comparison now and i guess that's the power of the flocculant when you when you understand how to use it then when it comes to the actual filtration media it turns out that in in australia you can buy both sand and aggregate that's specifically designed for filtration there's a couple of key suppliers in australia for this material one is from the logan river in brisbane a big supplier up there and another one where they do a lot of these systems in adelaide so he had to manually remove by hand all of the sand and aggregate from all the ibcs and then replace it with the new sand and aggregate when it comes to the actual plants themselves given that we live on a bit of a rural property we have a couple of dams many of these plants actually came from our dams so we have a permaculture consultant that we use that's lachy from tree frog permaculture in newcastle but when we put plants in the pool initially went opaque green you couldn't see through it at all so we went from a problem of silt where it was brown and you couldn't see anything to a problem where it was completely green with algae and you couldn't see through it and i i lost a lot of sleep over that but i kind of just put it on pause for a week or two and then i was walking up in my hallway looking out of the pool one day and i was like that looks a bit clearer and i thought well i'm just going to leave it and within a few days a week couple of weeks it went crystal clear and so obviously the and that was just as the plants were establishing and so i'm actually really glad that happened because it proved to me that the plants are actually had you know there was obviously introduction of biology but as the biology established and the plants established they consumed the algae and it went crystal clear and what you're seeing now is months and months later total water clarity entirely from the biology and from the plant filtration you can actually see there is some string what's called string algae in there and so we've since put some additional plants in that process those nitrates as well so just one comment on this roof structure and the way it relates to the pool ideally you don't want to have water from the roof directly going into the pool david always recommends as do we a first flush system we figured with this it's it's a small roof and we just decided to take the risk so we do have the water going straight so when it rains on the roof and it's actually quite nice so when you get a short shot downpour you end up getting a waterfall into the pool so that keeps the pool topped up and we have an overflow system when the pool gets too too high it overflows out the back we really like the separate planted zone to the the pool zone it kind of does create a nice space you get the same feeling of the pool and the organic water with a separate planted zone and you know we're super stoked with the result so just to sort of prove the point we're going to have a bit of a drink from the pool tastes amazing now we're going to go for a swim so my wife is the main one who actually wanted a pool to start with so i passed her how what's what's your view how is it to swim in the pool it's amazing you don't get the yuck of chlorine in your eyes and on your body and because we've got the bubble pumps the water is so aerated it's just so light feeling i just wanted to give a huge thanks to david for his support and we watched over and over many of his videos to to construct this and we're super stoked with the result and everyone who's been in the pool is super stoked with the result so it does work also a big thanks to lachie borges from borges building who did all the physical construction for us he did a phenomenal job and obviously being totally bespoke he was really flexible and and really appreciated his great work and also lachie from tree frog permaculture who assisted us with the planting and maintaining the biological balance so it is a bit of a team effort and as i said we're super happy with the result and can't recommend this kind of pool highly enough thanks again to everyone else online who post content that assists with this kind of project and hopefully this has helped to give back to the community hello i'm david pagan butler now i've been asked the question is it possible to have a separate swimming zone from the planted zone in an organic pool now an organic pool normally has the planted zone all the way around the outside and the swim zone in the middle this greatly simplifies the construction it also makes it fairly beneficial for wildlife however there may be circumstances where having a separate swim zone from the planted zone is really beneficial so i've mocked up a situation here where this tank is representing the swim zone and this one the planted zone and we've got the water circulating between the two just with the use of airlift pumps or bubble pumps now the swim zone what's happening is water is being drawn in from the planted zone via a pipe down there and this is filling up to a particular level and when that reaches a level of the exit drain water then drains into the planted zone and this circulation is what is filtering the water now in the planted zone i've represented the plants with plants but here you see i've used little floating islands of plants the more wild looking one is just lifted off a paving slab that was around the edge of the pool and the plants have been growing on that nice and neatly and i've just put a piece of wood underneath just to give it a bit of buoyancy and it's those plants have been sitting there quite happily for a week now and this other one this high-tech one i've got some insulation off cuts from a diy project i've drilled in a three inch hole and pushed in some plants this is mint so this is is actually one valid method of using plants to filter water so this is probably the simplest method to show how you can separate the planted zone from the swim zone so i hope you've enjoyed this little film and see you next time