Backyard Aquaponics
A place to discuss aquaponics

Hi
Im planning to start an AP system using a swimming pool as the fish tank, my target species is murray cod.

My primary goal is to grow fish, and the plants will will be both planted into the pool (to make it a little more pond like and attractive, im married so this is an important consideration) and also grown in beds, im thinking of herbs, cabbage, chillis, pretty much anything we can eat.

My biggest problem so far is deciding what kind of grow beds to make and what size pump i would need to get reasonable circulation as i dont want to incorpaorate any of the existing pool filtration system in case someone in the future would like to turn it back into a swimming pool.

I'm hoping to incorporate a refugium setup into the pool as i wold like to seed it with glass shrimp and possibly Pacific blue-eyes as an added natural food source and potentially yabbies as well, primarily for the fish to eat, not us. For this i was hoping to 'fence off' a section with a plastic mesh cage, probably containing sphagnum moss or other fine plants to provide a breeding area for the shrimp, the cage mesh will be of a size where the small 'feed' fish and shrimp can enter, but not the cod (or whatever species i end up with)

SO, i would like to pump the water up from the pool through the grow beds (probably expanded clay medium) i'd like multiple beds and possibly add an IBC at the end of the system, where it will flow back to the pool, to keep a second species of fish.

This is the embryo of my idea and i would love suggestions and ideas from all of you about how you would go about turning a pool into a micro-farm

Space: Next to the pool (45000L) is a small grass area roughly 4mx4m, inside the pool enclosure i have an area 2m wide on one side which has a 700mm wide tiled bench, 700mm high, this is a masonry bench and runs the entire length of the pool, my first idea is to put grow beds on the grass area, and then run pipes along the bench, which i could also use to plant in, into an IBC then back into the pool.

I dont want to discuss budget yet (there isnt much to discuss any way ) I would love an explosion of ideas as im really worried about maximising grow space inorder to filter the potentially very large amount of fish i could grow.

Thanks in advance for ALL replies, i will try and update with some pic's of the site soon

The Pool



Grassed area, complete with storm damaged greenhouse (approx 4m x 4m)



The bench alongside the pool

The pool, currently rich in algae due to the storm destroying the pump house and electrical connection, is built on a hillside so depending on the head height of the pump I get, I could have a lot of gravity to work with

Posting pics from tapatalk, sorry about all the gumpf it appears to have added and the uselessness of the captions, I'll try and edit when I get back to my PC

edit: Gumpf is only visible in the Tapatalk app it seems, makes more sense on PC

oh dear.!! a swimming pool into a FT...!!!
hope my son doesn't see this post, he is looking around for a disused pool about that size to do the same thing. he wants to go swimming with his fish..
hope it all goes very well for you.. might be back later asking you some questions.
cheers

There have been a few people who've done a pool conversion.

There are a couple of issues, like catching fish, nutrient dilution, but it can work.

Do a search on here for growing Murray Cod, they aren't the easiest fish to raise, they like to eat each other, and not the normal feed. But they can be grown, just make sure you know what you're walking into.

But beds, I'd maximise the area for the grow beds, have a long row of media bed(s), and have that flow into DWC beds, to a sump lower down. Just remember, the lower down the sump is, the bigger the pump will need to be to move it back up.

Hey, nice fish tank ! Maybe some shade sails and a UV clarifier could help with the algae.

..
Do I recall someone doing that superbly, on here..
But - I think that I recall that he actually used the pool as a space, not an actual fish tank..
So he built a floor over the pool and had GB's on top and all the workings underneath in the pool..
ie.. a more typical FT or FT's..
Likely a better and more practical way of using that area..

PS - if you had a particularly prominent "Deep End" you might be also able to use that.. ie part filled pool..
..
.

Hi Skidoo,
A project of that size without even thinking about the aquaponics system would need to achieve a very pleasing aesthetic appearance. I would put the design as a priority and employee a landscape designer first and foremost.. bridges, over water walkways, a couple of large tree stumps protruding from the pool (Fish tank) rocks covering some of that pebble mix concrete even a creek bed down on the bottom side which the GB's could drain into and have the water visibly running in the "creek bed" into a underground hidden sump... Vege's would be easily maintained & harvested from a level surface so maybe partly around the pool area..
aquaponics is getting fish to rely on plants and plants to rely on fish. it's similar to the work of an electrician or a plumber, the less you see the better it looks..!!

Aesthetics are going to be important here and my wife assures me she will be the project manager there, an important part of this experiment will be giving my grandfather a rod and telling him to catch dinner, as he is nearly 90 and dearly wishes he could still go fishing!

As far as cod go, I'm currently studying aquaculture at tafe and am lucky that my primary tutor has done extensive research with cod, she assures me that a lot of the current literature severely under estimates the suitability of cod for aquaculture, she is already bombarding me with cod husbandry info, I think she is more excited than I am. I would really like to learn more about this and be sure I will be sharing as many cod secrets as I can get..

My primary issues at the morn are:
1- can I get away with 10000lph pump? It is well below the recommended turn over per hour but as I intend to stock relatively lightly and use aquatic plants as well as grow beds I'm hoping I can find a balance.
2- I'm hoping for around 10m2 of grow beds, probably 30cm deep, clay or similar medium to add surface area, probably gravity feeding into 3x 10m sections of pipe which will be cut out to provide planting area, from here it will again gravity feed into a ground level sump which will over flow back into the pool. Without a diagram it's hard to picture (I'm working on one). But this would allow me to use only 1 pump, which will be pumping around 2.8m head. Is this even close to enough grow beds? Not considering the landscaping plants that will be in the pool to make it both aesthetically pleasing while also providing refuge for natural food.

3- how many cod would YOU try and grow? I'm think 50 fingerlings initially as proof of concept, aiming for around 3kg harvest weight, from intensive aquaculture systems I know they can manage around 80kg per 1000L, I have no intention of aiming for this. But I'm also hoping I can maintain a population of pacific blue eye and glass shrimp and these may add a noticeable bio load depending on there populations. Is this a reasonable amount of cod to aim for?

4- I'm planning to grow veges and herbs, particularly chillies as I have a small collection of heirloom varieties is like to grow in larger quantities, would small citrus be an option considering the many pot varieties now available? Possums are a problem here, so I am thinking of using greenhouses to cover the chillies and other possum favorites. The pipes I'm hoping to grow Asian greens in.

Soooo many questions, I have to try and work in manageable steps, I'm hoping to spend the next few months planning and preparing with the goal of getting fingerlings as early in the breeding season as possible.

I'm planning to measure up my space more accurately tomorrow and get to work on a selection of preliminary designs, I'll be working on a plan of the essential running gear first then develop a landscaping plan to make the pool area more pleasing later as even though the aesthetics are very important, I can't sacrifice functionality and ease of maintenance for looks.

Hi 23Skidoo, check out dandm's thread for a great pool conversion viewtopic.php?f=18&t=4396

Trout by the waterfall is a classic thread - not a pool conversion as such, but a series of large inground concrete fishtanks viewtopic.php?f=18&t=5504

Gunagulla in NSW has recent experience with murray cod that might be worth having a look at viewtopic.php?f=18&t=24153 - they can be fussy feeders

Dogdoor has a lovely set up with a purpose built courtyard pool with a vertical wall garden and vegies up on the balcony above viewtopic.php?t=15481

Shelly S has recently done an above ground pool conversion viewtopic.php?f=18&t=24575&hilit=Shelly

I think BuiDoi was referring to Slowboat's pool to pond conversion - great thread viewtopic.php?f=18&t=16397

Happy reading and planning

10,000lph pump. I don't think that would be half enough, and a head of 2.8mtes would cut it back dramatically, I use a 7,000lph single pump on a level ground feeding 3 growbeds and 2 IBC's with fish with another 2 GB's about to be installed, and i think ill have to get a bigger pump...(FT is 5,000ltes) GB's are about 20m2
Circulation in the pool would also have to be considered..
To be very honest skidoo, you won't even know that 50 Murray cod fingerlings are in there for at least 2-3 years.
I have 40 MC fingerlings in an IBC for over 4mths and i could still put them all in a coffee cup..
To get the ball rolling and for your grandfather to get in some fishing time, I would be putting in 100 Rainbow trout fingerlings, they will grow extremely fast, put them in asap with some good aeration after water tests and you would be surprised how much action on the surface and how soon your Grandfather will be hooking them...
Another issue which you may have is the nutrient levels in the pool may never be adequate to feed the plants. Seasol, blood & bone, iron, potassium, etc etc will need to be added for some time to come until your fish are producing enough waste to even register on a water test... probably babbling a bit....maybe excited as much as your tafe' teacher

The problem you'll have with cod in a fish tank that size is that their predatory nature will mean you end up with perhaps 2 or 3 after they eat each other. Check with your lecturer, everything I've ever read and heard about MC says that you need high densities to stop them eating each other, and you can't have a high density of them in a swimming pool.

hey earthbound,
you may know this, I read that MC are one of the fastest growing fish for the first 18mths or so and then they put the brakes on .! is that correct.? i have RT here that have nearly tripled in size (nearly 100-130mm now) while the MC are virtually the same 40-50mm as when i got them 4 mths ago.. water temp has alot to do with it I know but just seems rather strange to me..

All fish grow very fast at the start when in ideal conditions and getting lots of feed.. My guess would be that the MC aren't getting as much feed or eating as much as the trout, and/or conditions aren't as ideal for the MC as the trout..

From talking with my lecturer last night I'm confident cod can be grown very fast for the first 12-18 months, but diet is essential as they can consume enormous amounts of food compared to other fish and produce large amounts of waste as a result, this is part of the reason I want to stock with blue eyes and glass shrimp as well, when I get her MC food formula I'll share it here as she makes her own food based on carp.
Aggression can be eased with high sticking densities, which is impractical for me but can also be helped by providing hides for the fish and they will live quite close together providing food is plentiful and they have a place to call their own.

More research to be done yet...