Aquaponics - New growbed flow control

I few days ago I created and installed all the required bits to control the way water enters and exits my growbed.

All this is probably overkill as a lot of people get away with just dumping water at one end, and draining from the other, but there's a fair chance that at some stage down the track I might try to make this system ultra low energy, so I thought I'd design it so the water can move very freely through the browbed, and so it doesn't leave any areas that don't get enough flow. If I go low energy, that might mean low flow, so I designed it to what I think is the best way I could.

The plan is to have the water enter into a submerged pipe at one end of the bed that has a lot of holes in it, and exit via a similar, submerged pipe at the other end. This way the water will enter and exit evenly throughout the width of the growbed ensuring that no corners are left to go stagnant. With high flow, this wouldn't normally be a concern, but I wanted to make sure I had lots of options for the future.

After a bit of experimentation I discovered the quickest and easiest way to make holes in PVC pipe for water flow was with an angle grinder.

Just a normal metal cutting blade does a pretty clean job of cutting a lot of slots in a 90mm PVC pipe.

Just tap it onto the PVC quickly and it works a treat. A one second cut is perfect. Three seconds will burn it.






Slots are a must when using the clay balls for media as if you drilled holes, the balls would block them all.

All sized balls will block all sized holes regardless.

Go with slots.

The end result looks like this and only takes around 5 minutes per meter at most.

I cleaned it up with a little sand paper and added end caps and an elbow.

I cut a hole with a hole saw so that I could add a stand pipe that would go through the elbow, then continue on through the growbed.

There's no great need to make these joins exact because you want water to seep in all through this bit of kit.

I  found some fittings that for some reason have a tapered thread.

When I got them home, I found that the things they screw into don't, which is kind of strange.








The original idea was to cut a hole through the growbed, and screw the two pieces together from either side to lock the fittings on tight.

Because of the taper, I ended up just making the hole in the growbed really tight, and screwing the fitting in really hard so it cut it's own thread into the growbed.

It seems solid enough.

This is what the finished drain looks like. This will drain water from the growbed back to the sump.

A pipe will be fit into the recess at the bottom, so that even though the water enters the drain from the bottom of the growbed, the water will exit the device at a bit lower than the top of the growbed.

I cut a hole with my hole saw into the bottom of the growbed.

This is an oddly scary thing to do.

Shiny new water tight containers don't lend themselves to be holed without causing some distress to the new owner.

I cut the hole slightly smaller than it needed to be, and then hand filed the rest so I could be sure of a very tight fit for the threaded component.

Once coaxed through the hole in the growbed, the standpipe was cut to size, and pressed into place without any glue.

There's no need to glue it because if it leaks, water wont actually leave the system, and there might come a day when I want to adjust the level, or change the system from constant flood to an auto siphon or something.

The drain assembly looked like this when fitted.

The standpipe runs through the growbed on the left hand side.

The other end was completed in a similar manner, but this time with a central inlet because there was already a hole in that position.

This is where water will enter the system from the fishtank.

And that's it.

The growbed part of the system is complete.

It's worth adding plastic caps top the top of the inlet and outlet media guards to keep the clay balls from getting in when your digging around in the garden.





Like I said, it's probably overkill to make the inlet and outlet pipes like I did here, but it should make it just that little bit more efficient.


120 Things In 20 Years isn't above pretending to make a new growbed when really I made it more than a week ago.

Aquaponics - Flow meter

I got up in the night a week ago, went for a stroll through my house, and promptly fell over a lump of furniture nesting in my hallway. The last few weeks has seen us deciding that we really don't need a ... whatever you call that room with couches and a TV in your part of the world ... living room, lounge room... something like that if you speak English. Anyway, we decided we don't do enough "living" or "lounging" to really need a room dedicated to it, so we filled it full of floor to ceiling shelving, some desks and benches, and turned it into something more like a factory. A factory that doesn't actually produce anything, but does a heap of product development.

We figure when we want to entertain, we'll just do it at our guest's house.

The result of all this that meandering about our house, is a river of transient furniture acting as flotsam and jetsam and nesting where it feels most comfortable, or simply where it last got stuck.

The result of that, is I tripped over an upturned thing with casters on the legs and impaled myself in the lower rib cage.

The next day I went to a doctor with a temperature of 39.7 c.

Who knew falling down gives you a temperature?  The doc thought I had ruptured my spleen so he suggested I go to hospital. The hospital decided I had three cracked ribs and pneumonia. A week later they finally disconnected all the feeding tubes, the morphine drip, and the catheter and let me go home.

The interesting upshot of all this, is that as a result of being given some kind of lung exercise device, I now have an excellent flow metre for my aquaponics system.


Which is nice.

Thinking - Beam me up Scotty

Dear The-President,

I'm reasonably sure that the pressure difference between the Enterprise and (statistically speaking), pretty much every planet's surface, would result in a lot of sinus pain and some scenes involving explosive snot.

I feel these scenes were conspicuously absent in the filming of the Star Trek franchise during beaming exercises.

I further feel that in the interest of reality, this should be easily rectified.

The absence of snot is the absence of reality...

Boomshanka.




120 Things in 20 years - It's possible that I have a cold.

Aquaponics - New growbed

I have a shiny new allotment of auqaponics real estate!

Yay me!

With a huge amount of help from Mrs. 120 Things, we added two submerged sections of 90mm PVC as inlet and outlet drainage media screens.

We also cut holes in the top of one end of the BYAP grow bend to allow water in from the fishtank, and the bottom of the other end to allow a standpipe to be fitted.

Then we fitted the standpipe. Basically a short length of pipe that sets the depth the water will sit at, by draining the growbed from the top of the pipe, out through a hole in the growbed.

Or in normalspeak, a plug with a tube stuck in it.

The result of a lot of picking through the media (clay balls) to remove all the rubbish that comes with buying second hand media, was this very nice looking growbed. (the growbed was second hand as well)

Working with a purpose built growbed with purpose built media is soooo much nicer than working with home made stuff. I'm all for tinkering and DIY, but if you just want a garden, this pre-made stuff is great. I have no connection with Backyard Aquaponics other than existing on their forum* (as BullwinkleII), but having bought one of their growbeds (second hand), I feel very comfortable recommending them.

Getting there.


* and winning my pump and some other stuff in one of their photo competitions.

Aquaponics - Rain rain it's ok

I was planing a bit of a build post on setting up my new improved aquaponics system, but the heat wave we have been having of up to 44 C (111 F) was interrupted this weekend by two days of rain that sunk our fringe festival.

But I like rain.

For one thing it's nice that 44 C, but it also lets my put off doing things that I really should.

44 C days also let me put stuff off, but they are less pleasant to sit in.

Rain is much better.

So my new system looks like this...

I'm in the process of siphoning it out, but it collected enough water to fill it to the 3/4 mark.

But I think I've finalised a plan for my new system.

I've never been a big fan of removing solids from an auqaponics system because I really like the way it forms an integrated system, where the fish waste feeds the plants, but I thought I'd have a go at it because years ago someone thought it was a good idea.

The only real problem I have with removing solids is that it seems like a waste, but I figure if I can use the solids in the system, it will still fit within my comfort zone.

So the plan is...

• Make a swirl filter to collect solids
• Build a bell siphon into the swirl filter with an adjustable (height) stand pipe
• Set an outlet on the swirl filter such that it can dump water from the surface at the same rate that water is entering from the fishtank. This way the siphone will never trigger under normal operation.
• Make a stock tank float valve so that it adds water from the tap if it gets below a certain level 
• Make a Shishi-odoshi, which is a thing you might find in a Japanese garden that water trickles into, and occasionally goes "Doonk". It's basically a length of bamboo that is mounted at 45 degrees on a pivot point just a bit lower than it's half way mark. Water enters the pipe from the top, and when it gets full, the weight at the top causes it to pivot and dump it's water. The nature of the universe being what it is means the device dumps all it's water, because once it's commited to the dump, the weight of all the water shifts to the (now) bottom end. It also hits the ground and makes the "Doonk" sound that is apparently useful to scare deer away from your garden. Also apparently, Shishi-odoshi (鹿威) means "scare the deer" in Japanese. I dont know why you would want to do that. 
• Make an automatic water topup system for my sump tank so that when the water gets low due to evaporation, it will add a bit. There is such a thing as a stock tank valve that makes sure your cows always have a full trough no matter how thirsty they get. I'll use one of those. They have a float that regulates when water can flow. I'll use that in the sump, set so it triggers at my minimum low tide mark, then rather than dump that water into the sump, I'll dump it into the Shishi-odoshi. When this happens the water will continue to flow from the tap until the sump is filled again, so the Shishi-odoshi will fill reasonably quickly, then dump suddenly. 
• Build a cup of PVC with a half inch hole in it so that it surrounds the standpipe from about halfway up and is higher than the standpipe by a few inches. 
• Drill a half inch hole into the standpipe at the bottom, of a size that would mean the water being sucked into the standpipe would be roughly equalled be the water entering the cup. ie it wouldn't just instantly drain and halt the siphon once triggered. 
• Direct this dump from the Shishi-odoshi into the cup surrounding the siphon, and it will instantly trigger the siphon. 
• The swirl filter will collect the solids at the bottom in the centre, so only a small amount of water needs to be dumped to empty the solids from the system. Perhaps only a litre or two. 
• The dump of solids from the contraption (and this is by far my favourite bit) will drop directly into my soon to be newly constructed worm farm. My fish go crazy for worms. 

The beauty of the system is that the hotter it is, the more active my silver perch are. They eat way more in summer than winter. The result will be in winter when the fish and worms are less active, the worm farm wont need or get much water, and the system wont need as much topup water. 

The result is that it should regulate itself perfectly. 

in summer...

• worms are more active and eat more
• the fish are more active and produce more waste
• The worm farm needs more water (or at least can handle the extra litre or two every day) (mine will be a fairly large worm farm. I'm thinking of using a blue barrel)
• the system needs more topup water to replace evaporation so the Shishi-odoshi will trigger more often, and so supply more water and solids to the more active worms.

The worms eat my kitchen scraps, and fish poop.

The fish eat the worms, some duckweed growing on the sump, the scraps from the system (cuttings, root balls etc) and some store bought feed.

The plants eat the fish solids.

I eat the plants and the fish.

Everyone is happy.

Except the plants and the fish, the duckweed, and the worms. 

120 Things in 20 years Where I am everyone.

Aquaponics - Automatic solids removal

So this...

out of the blue

A while ago... What I think is a year in Bullwinklle time... I decided I'd not use the invention engine for a year to see if it made any difference to the quality of the stuff I create. I have no real idea if it it has, but I'm now officially giving up on the experiment.

It feels a little like I've had one hemisphere tied behind my back.

So now I've decided to set two tasks allowing full access to the invention engine process.

1. Get sticking rich.
2. Contribute something to my garden that might be useful to someone else.

The two are in no way connected, and because I have no idea how to get sticking rich, I thought I'd start with the aquaponics system, and leave the wealth part for another day.

I suspect leaving getting sticking rich for another day might be a theme in my life.

anyway ...

I've been playing around with the idea of making a farm to grow escargo for many years. I figured this might by the thing I could put some research into and come up with an idea or two. My ideas put to the engine have all been based around using a bell siphon to flush a grow bed of snail solids by drowning the entire farm...say... once a day, by completely submerging the grazing feed (lettuce etc) in 30cm deep of water to wash away the snail's solid waste.

The plan looked something like this...

Picture a 30cm deep BYAP grow bed with 15cm of media, and a 1cm wire mesh stretched across the top. The escargo would live in a cage on top of this grow bed. Planted in the growbed would be green leafy plants that snails liked, and that could survive being eaten from the top once they reached a height of 15cm. Lettuce etc. The plants would grow to 15cm height, then they would be grazed by the snails that would be housed in a cage that sat on top of the lettuce cage.The lettuce would continue to grow, and via some magic that I would figure out with the invention engine, the solids would be rinsed every so often with the rising tide of an auto siphon (or something)

Got it?

It doesn't matter, because that's not what I'm going to do.

It turns out that if you read through own threads on forums, you find you made some other promise to make an aquaponics system that removes solids automatically.

Oh well.

Unfortunately for me I think I might have a go at this as a project.

I would like to state at this stage that I think this is an entirely pointless thing to do. I really like the way aquaponics works as an almost closed loop (if you invite your fish food manufacturer into your loop).

The balance is what makes it so appealing.

But that is also what makes it appealing as a task to set the invention engine.

Sorry universe.

So that's it...

How do I make an aquaponics system that removes solids?

Eughhh! (with shaking head)


Ok...


How do I make an aquaponics system, that I don't hate, that removes solids?


I already have some stuff that might be relevant from when I made a swirl filter (somebody eles's invention), but made it with a built in autosiphon. The problem with that is it triggers all the time and dumps a lot of water with the solids.

Now that I think of it, I might have already come up with some other useful stuff as well.

Perhaps this test of the invention engine will just prove that I should have paid attention the first time around.

And now I remember the deer scarer.

Perhaps I've already collected all the bits I need.




120ThingsIn20Years thinks this might be a bad way to come out of semi-retirement (Eughhh!)