Planning a natural pool

coolbeverage

Hi everyone! This is my first post here. I have a very green swimming pool that is roughly 20k gallons kidney shaped and has not been in service for 4 years. There is a good amount of sediment at the bottom that I have been removing by way of pool net over the past few weeks and it appears that I am making progress. I would say that 90% of this is dead or dormant algae, and the water as you would imagine is quite green. There are mosquito fish in there that have been happily living and reproducing for several years (and controlling mosquitoes effectively)

I have convinced the owners of the pool/pond (my parents) that the best thing to do is to create an oasis using natural methods and the like, and they are onboard so long as it doens't cost too much or become too much in the way of maintenance.

Some more relevant info is that we have a very steep slope above the pool as well as some area below the pool, either of which could be used for growbed/sump areas.

My idea at present is to pump the water from the skimmer up to some grow beds on the slope (southern facing) and then cascade this water back down to the pool perhaps through a solar heating panel and/or a uv filter.

Here are some questions for you all...

1. Will I be able to remove the algae without draining the pool? I am dilligently working to remove the scum from the bottom and I believe that I can get most of it, however, I am unable to stop the individual cells from going back into the water through the net, and at some point it will be necessary to kill it (shock with bleach) or UV filter it or something. The plan right now is to get as much out as possible, and then shock everything to kill all the algae while constructing the beds etc. The reasoning is that we cannot afford to crack the pool from groundwater if we empty it, and it is very expensive to refill it if we empty it. What would you do?

2. Does my plan to use the slope make sense? How much media will I need to filter this much water? I am thinking that I can construct some grow beds that are individually plumbed and feed directly back to the pool, or make them go from one to the next all the way down before flowing back. Is one design better than the other? Keep in mind that in the end we plan to have minimal fish for the purpose of controlling bugs and algae (tilapia or cats?), providing some fertilizer for the plants, and maybe some pretty ones for looks/eats. We do want to swim in the pool during the summers.

3. There is an existing sand filter. Is this useful in any way?

Thank you! Any and all comments/ideas will help greatly. I am curious about the UV filters especially at the moment, and any experience anyone has had with this type of thing.

Charlie

Welcome to the forum :wave1:

MacGyver

There are a number of ways that you can go about doing this. One way is to treat it like an ornamental koi fish pond and make the water crystal clear with UV filters, bio filters, grow beds etc. The other way is to go natural and forget about removing all the algae and sediment at the bottom. Then of course there are hybrid combinations of the above two ideas.

A number of problems arise either way but that does not mean it can not be done. If you want the water to be crystal clear then you will more than likely need a UV filter, bio filter or a really large grow bed. You need to be pumping from bottom drains rather than the skimmer as all the fish waste will eventually sink to the bottom. The problem with big pools is that the water needs to be pumped through the system within a given amount of time and this is costly.

Alternatively you can just let the algae and sediment stay in the pool as this is part of creating a natural miniature eco system. You can still pump water to a grow bed and grow vegetables. If you do it the natural way, the amount of fish you can stock is less. I have seen a number of examples of this being done i.e. large natural pond pumping to grow beds and growing vegetables, however I have always wondered why they work so well since I'm pretty sure the fish waste would be stuck at the bottom and the bacteria would be anaerobic rather than aerobic. If anyone else on this forum can educate me on this that would be much appreciated. I initially thought that it would be necessary to remove the sediment at the bottom but it turns out that it's a good idea to leave it there. (I'm not sure how well the bottom drains would work under these circumstances though) Maybe a new pump has to be added that is a mid level intake?

Here are some examples to look at:

http://kilk.com/pond/

viewtopic.php?t=4396

Pool to natural pond:

ccBear

Go to www.permaculture.org.au and search for Eco friendly swimming pool.

MacGyver

http://permaculture.org.au/2011/10/28/u ... ss-report/

http://permaculture.org.au/2009/07/21/c ... fish-farm/

MacGyver

It would be great if a pool could be used as the fish tank with some added grow beds for growing vegetables but there seems to be different schools of thought when it comes to actually doing this. Since a pool is such a large body of water it is difficult to pump all the water through a bio filter within a certain period of time as recommended without the cost skyrocketing, however the large body of water could also act as a buffer which means that the water does not actually have to be circulated as quickly and a smaller pump could be used. Does this then mean that the vegetables in the grow bed will not get enough nutrients and so while the fish might be fine, the available nutrients would not be harnessed to their full potential?

I'm thinking that the fish stocking density in a large pool to pond aquaponics system could be higher than a regular aquaponics GB to fish stocking density ratio, so you could have a relatively smaller grow bed because there is such a large buffer zone created by the large body of water. The reason for using a smaller grow bed compared to the amount of fish is to counter the huge body of water buffer so that there is enough nutrients for the vegetables. The trick is to find the right balance so as to maximise vegetable growth. There are a number of challenges to consider however it can definitely be done.

@ the more experienced in this forum: If I ever say something misleading or totally incorrect please let me know.

MacGyver

bunson

Is it just me, or is the audio in YouTube videos fritzed lately?

MacGyver

bunson wrote:

Is it just me, or is the audio in YouTube videos fritzed lately?

Audio is working fine here bunson.

MacGyver

@ bunson Come to think of it I had some trouble with YouTube audio a couple weeks back i.e. some videos had no audio.

coolbeverage

Thank you all so much for your help!
Can anyone give me an approximate size of biofilter/gb so that I can wrap my head around it a little better. Initially I was thinking of a smaller pump circulating through some 55 gallon drums filled with sponges or similar and falling through a gravel bed maybe 10lx2wx2d (in feet) emptying into a pond with water plants and spilling back into the pool via waterfall. Problem is, that seems too small. The sand filter we have is smaller than a 55 gallon drum, but it is designed to be used with chemicals.

Yes I want the water crystal clear,
No I do not have the need to stock lots of fish, but the ability to do so (or to easily expand on the system to do so) would be awesome. I also do not need to grow lots of plants, i would like to, but that is secondary to making the pool shine.

sediment at the bottom won't go over well. I should be able to suck using the existing pump from the bottom of the pool, but i need to get all the rest of the sediment out first. There are a bunch of potato bugs that live in that stuff when i pull it up.

The pool owners are looking for low maintenance, relatively cheap, but very aesthetically pleasing. (I know, I want my own island too) But I think it can be done with the right design. We are willing to build some concrete beds into the side of the hill, but I sure would want them to work if we go to that trouble.

So the short term goal is to get it swimmable asap, which will give me the go ahead to make this a large scale ap system. Anyone know of a good way of removing algae from solution efficiently? I'd love to hear it....

kbarrow

bunson wrote:

Is it just me, or is the audio in YouTube videos fritzed lately?

Scott,
Sometimes I problems like that and a blue tone on the video when hardware acceleration is activated in the flash player. For some reason it occasional goes back to that setting, I right click on the video, disable the hardware acceleration and everything goes back to normal.

bunson

Thanks Kenny. There's a well known Flash problem with a specific directory, but this isn't the issue in my case. I reinstalled an older version of my (crappy) Realtek drivers and it seems to have fixed the problem (for now)??? Fingers crossed.

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