Backyard Aquaponics
A place to discuss aquaponics

G'day all.

Thought I'd start a build thread to keep track of where I'm up to and get some help and advice along the way.

I 'discovered' Aquaponics about three weeks back whilst looking for cheap IBC's for storing seawater for my marine aquarium. A bunch of sites relating to AP turned up in the search results and being a keen aquarist it had instant appeal. So after absorbing as much info as I could by reading the forums here, I decided to embark on putting a system together.

My idea is to put a budget system together utilising as much from the junk pile as possible, and where I have to buy some parts to try and be as cost effective as possible.

The design is based around a 1250 litre kids pool as my fish 'tank' and twelve 55 litre containers as my 'grow beds'. Both were chosen because of their cheap cost and resemblance to other more expensive AP stuff. The beds will be mounted on a frame over the edge of the pool and the whole thing will be clad in stuff from the junk pile to make it look pretty as it is a bit of a feature in the garden due to its location.

If the description is a little hard to vasualise, some pics will probably make it easier.

Here's the progress so far...

Grow beds are 55 litre storage containers - 300mm deep. These were $5 a pop from cheap as chips.



We cleared a spot in the garden. It's part shaded part sunny so good for a variety of plants.



Figuring out if the pool will fit. $95 from Bunnings for a 1250 litre pool, it comes with a shade but this will not fit once the grow beds are in place.



and the kids testing out the location of the grow beds



Laying a path around the area with bricks reclaimed from elsewhere in the garden. This will stop the dust and dirt kicking up.



Path nearly finished - time for another test fit



The last shot shows the basic layout. The beds will be mounted above the pool so that they can drain directly into it plus this will give the pool some shade. It will also allow me to clad the outside and provide a bit of a barrier to prevent the kids from diving in.

I've opted not to install a sump so I will see a bit of variation in water level in the FT, in fact with all beds operating flood and drain potentially half of the FT could be in the GB's so I need to come up with a solution for this. I've considered running half (or more) of the GBs as constant flood as it seems that many have had good results with this, I've also considered staging the GB's so that only four run at any one time but haven't figured out a cheap elegant and reliable way of doing this yet.

I did consider using 4 pumps on timers but having already ordered a 5000 litre pump it was a bit too late. I will figure it out at some point.

At the moment I'm trying to track down a source for expanded clay in Adelaide. I know that other mediums might be cheaper but with the design that I have planned the weight will be an issue.

I'm aiming on getting it ready for the end of the month so that I can stock up with silver perch or at least that is the plan.

So I have lots of questions on what to plant, when to plant it, how to plant it and other real basic stuff that I should have probably known before embarking on this journey. I've been reading a couple of good veggie books - 'The Australian vegetable gardeners diary' and the 'kitchen garden companion'. Both have real good info on managing a dirt based garden, what to plant and when, companion planting, how much to plant to feed family of four and other great stuff, but I don't know how, or even if this relates to an AP setup.

I'm sure I will figure this out as I go along, hopefully with a little help from BYAP.

Next up I need to level the ground and start constructing the frame.

Mick.

Won't that design make fish access difficult? Maybe you should skip one tub for a "keyhole design" of sorts...?

Yes it will certainly hinder access, but this is an intentional feature as I have a two and a three year old that I don't want to go swimming.

I'm guessing that there's usually little reason to get in there too frequently although I'd be interested to hear what kind of maintenance people are doing to require frequent access (apart from feeding of course). It should be fairly easy to see the pool across the tops of the GB's so a daily visual on the fish should be possible and The tubs can be very easily lifted out if required which will give direct access to the pond underneath for more close up and personal stuff. There's also the option of waders or a snorkel if I need to get a closer look

Ok. My first question...

What are people using instead of bulkhead fittings for the stand pipes?

I want to avoid using a 'proper' tank type bulkhead fitting as these are too costly due to the fact that I need 12 of them.

Any ideas?

Use a standard 40mm "plug & waste".... get a 25/20mm reducer... and cut a standpipe from 25mm pressure pipe....

If you decide to run constant flood... then you'll have water returning all the time... and you can adjust your tank level up a bit... and then it'll remain constant... unless the power goes out...

If you go timed flood & drain... the tank level will drop a bit when the pump first starts... but (remember 2 x 6mm holes in the standpipe)... the grow beds will begin draining back to the fish tank immediately...

If you want to use flood and drain you could set up two pumps to run alternately, or you could use an indexing valve with one pump. Either solution will maen much less fluctuation in fish tank level.

+1, easy as.

Perfect, thanks for the pic too. Made it much easier to visualise

I'd read elsewhere in the forums about an indexing valve, how do they work? What would I need to trigger it?


Mick.

Every time the pump comes on the indexing valve selects the next outlet along to push the water into. You can get valves with different numbers of outlets as well.

So all you need to trigger it is a simple timer - every time the pump comes on the next set of growbeds would be filled. All you need is a timer that can turn on and off many times a day.

Indeed... the aquaponics valve comes in 25mm & 40mm inlet/outlet options...

The 25mm range has 4,6 & 8 port options... the 40mm has both 4 & 6 port models...

Camsets are available that allow for outlet ports to be "skipped"...

Thanks guys,

Awesome, I recon that will be the go. If I use an 8 way unit, and run 4 beds on constant flood, I can then cycle though the others individually. Or perhaps a 4 way and connect the beds in pairs, or a 6 way and run 6 as constant flood. Hehe. This should do the job nicely. Will have to sit down and work out the best configuration to use.

Do these work well with 'dirty' water? My planned plumbing layout would have the valve directly connected to the pump which will (hopefully) pick up lots of poo from the centre of the pool.

Mick.

Before you get carried away with talk of 6 way valves, investigate your timer options. If you want a 15 min on, 45 min off cycle, then that means you can have at most 4 outlets in the rotation. It also assumes you can get a timer that can do 15 min on, and a couple of seconds off.

If you can only get a timer that can do 15 on, 15 off then you are limited to a 2-way indexing valve (or a 4 way valve with opposite ports plumbed together.)

You won't get much benefit in tank level from having more than 2 ports anyway.

Vdubber... I think you need to step back a bit...

Although you have 12 grow beds... they're very small, probably only 200L....

Any flood & drain configuration isn't going to draw down your tank for that long... yes it will fluctuate a bit....

But frankly I wouldn't worry about it.. and just go timed flood & drain.. which means water begins returning to the tank almost immediately...

You wouldn't really be able to run "constant flood" with a sequencing valve... as the valve is designed to only output through a single outlet port at any one time... which would leave the grow beds "undrained"... or constantly flooded.. until the next timer/sequencer cycle...

Not a completely bad thing... but if you're running a timer based configuration... and/or worried about tank draw down... and for aeration reasons... I'd either just run the whole system as continuous constant flood... or timed flood & drain...

In terms of the valve and "dirty water".... the valve was specifically designed/modified for aquaponics conditions... that's why it's called the "aquaponics valve"...

I've been using several of them since I first began the design modification process... nearly 5 years ago...

And I'm about to expand/reconfigure my timed flood & drain system... single pump, 4 way aquaponics valve.... 12 x 500L grow beds... (yes this does require a sump)

Depending on your tank size... you can run 6-8 x 500L grow beds ... on a 3000L fish tank... (see the BYAP "Deluxe" systems)

A fish tank that size is typically higher than the grow beds... and you need a sump return.... but if the tank is buried... you can direct gravity drain...

Here's a 6 x 500L grow bed timed flood & drain system..... (3000L tank/1000l sump)... (well dual systems actually)...

You're essentially correct... a 15 min incremental mechanical timer.... will only allow 4 sequencing cycles per hour.... but any perceived limitaions are easily overcome by placing gow beds into banks of 2,3, 4 etc...

My current redesign will use a 4 port aquaponics valve... to serve 4 x 3 banks of 500L grow beds...

The aquaponics valve only requires an interruption of flow of <2 seconds... so a digital timer alone.. can easily service many, many more beds.. even individually...

The aquaponics valve can even be "daisy chained"... and in conjunction with a digital timer... can service (allowing for tank size/drawdown).. a vast array of beds...

A 15 min incremental timer.. with a 4 port aquaponics valve.. will see each individual bank of grow beds.. or individual bed ....flooded for 15 mins.. and drained for 105 mins...

If you pair the plumbing of the aquaponics valve outlets to each bed, or bank of beds...

i.e opposite valve outlets to a common bed delivery line... then you cut that rotation period in half.... basically back to 15/45...

The options are endless....

But in Vdubbers case... with the size of the grow bed containers... I just don't think a sequencing valve is required, or necessary....