Aquaponics Adventure Mark II

Aquaponics - 3 Comments » - Posted on March, 26, 2008 at 9:12 pm

Firstly, lets make sure you all know what aquaponics is all about. I won’t explain it well enough, so I’m not going to try. Lets just say it’s a cycle where fish and plants thrive in a symbiotic relationship where the fish provide the plants with fertaliser, and the plants clean the water for the fish. If you want to know more see these sites:

  • Joel Malcom has headed the craze in Aus and his site contains plenty of info as well as a lively forum. He also wrote a book for beginners which you can buy.
  • This free magazine is a great publication from the forum members at BackyardAquaponics, and a great intro to Aquaponics .
  • This page contains a pretty good summary of the process.
  • This guy seems to summarise the pros fairly well.

Little do you bloggers know, but my first Aquaponics adventure was a bit of a failed attempt. I think the main problem was that I was living in a rental, and thus I’d set it up at my parents house. This created all sorts of difficulties to do with maintenance and monitoring. It didn’t help that it was my first system and was flawed by design. Basically, if the power went out, the pump in my sump wouldn’t turn on and I’d lose about 500L of water into the neighbours yard. The fish were fine with this, but when I topped up my fish tank with water from the rainwater tanks, it changed pH, temperature, water hardness and all sorts of other parameters which the fish really struggled to deal with, and died.

So we bought a house and I’ve started setting up the Mark II system at my house. It’s what the BackyardAquaponics crew call a CHIFT PIST system – Constant Height In Fish Tank, Pump In Sump Tank. Basically the concept is that you have a large sump, in my case, 500L, which is the lowest point in the system (the sump) and houses a pump which pumps water up to the main fish tank. The main fish tank (in my case 1000L) overflows and the water runs out into the grow beds. These drain back to the sump, closing the loop. With this system, if the power ever cuts out, there is no circulation, but there is also no loss of water. So essentially it is more robust.

Here is a photo blog of my work in progress:

This is the site of the system, it’s behind the shed and that might throw up a few problems of it’s own (it might not get enough light) which I’ll have to deal with later:

Below we have some stills showing the back breaking work of digging the sump into the ground. This provides insulation and ensures that it is below the drains of the growbeds.

Below is the sump and fishtank in place. The sump is the green thing, the fishtank the black thing.

Then we have the growbeds. These bathtubs are filled with rocks which act as the biological filter for the system. In the photo below I show how I’ve raised them off the ground so that I get a height difference between the sump and the growbeds and also raise them up to a comfortable height to work with.

For draining the bathtubs I use a regular ol’ bathtub drain with the center thingo popped out.

Then a 40mm PVC adapter freakishly slots in that and makes a great seal.

And then my standpipe will fit into that (although this picture just shows some uncut 40mm pipe and the bathtub with some water in it – proof of concept though).

Put on the plumbers hat, plumb the overflow from the fish tank to the grow beds, and the drains from the growbeds to the sump. I use T’s in most places instead of elbows as it provides a “view port” into the plumbing and prevents any siphon effect from forming.

Then you have to wash the rocks to get all the dust and crap off them.

And you end up with two filled grow beds!

This is the reason you wash your rocks: GUNK. Look at this stuff, you really don’t want that in the bottom of your growbeds.

The concept behind a standpipe is that it sits inside the grow bed and drains at a steady rate. So when you have water coming into the beds at a greater rate than it is draining, the grow beds fill with water. When you turn off the water, the grow beds slowly drain. So that you don’t overflow the beds, you make it so that if the water ever gets above the level of the rocks, it just overflows into the standpipe and thus the growbeds can never overflow.

My standpipes have two small holes drilled in the bottom of the 40mm PVC pipe connector, and a large section cut out of the top with a PVC “C” to provide an adjustable overflow level control. In the photo below, the bottom of the standpipe is on the left, the top on the right. The bottom of the standpipe (left) slots in the drain of the bathtubs as seen above.

Now we don’t want the standpipes getting all clogged up, and we want to be able to remove them for maintenance. So we put in some 90mm PVC to protect it. We need to drill holes in this so that water actually comes through to the standpipe. Below is a picture of this 90mm PVC pipe sitting over the drain of the growbed without the standpipe in place (but that’s where it would go).

This is showing the water returning from the growbeds to the sump.

This is a work in progress, and as such there are still a LOT of things I need to do to get this system up and running. I’ve actually got a fair bit of it done and just not taken any photos, so we’ll see. I might just update this article, or I might post it in another. Either way, you’ll hear more about this aquaponics adventure in the next couple of weeks.

Mad H4x0rs

Site, Software - 1 Comment » - Posted on December, 5, 2007 at 8:14 pm

One of the fantastic things about having a blog that nobody reads is that any anomoly quickly shows up. If I hit up the statistics page for my domain, I see this:


Search Keyphrases (Top 10)
14 different keyphrases Search Percent
pps til exe 6 31.5 %
replacing 306 cabriolet hydraulic roof hoses 1 5.2 %
bernard hill 1 5.2 %
everquest midi download 1 5.2 %
replacing 306 cabriolet hydraulic roof houses 1 5.2 %
peugeot 306 cabriolet hydraulic ram 1 5.2 %
vp62 codec download 1 5.2 %
download decode for pps 1 5.2 %
vray plugin rhino error 1 5.2 %
how to fix peugeot 306 cabriolet roof 1 5.2 %
Other phrases 4 21 %

So my site was found 6 times by searching for pps til exe.

Pages-URL (Top 10)
16 different pages-url Viewed Average size Entry Exit
/grandad/feed/ 23 35.17 KB 23 22
/gemmell/replacing-306-cabriolet-hydraulic-roof-hoses/ 17 21.53 KB 11 9
/gemmell/gallery/tmp/download-freeware-.pps-to-.exe.html 11 13.82 KB 6 6
/gemmell/ 7 35.03 KB 3 5
/ 2 1.37 KB 2 2
/gemmell/2007/04/14/goals-dreams-needs-and-lucid-dreams/ 1 16.00 KB 1
/gemmell/gallery/aquaponics 1 20.71 KB
/gemmell/replacing-306-cabriolet-hydraulic-roof-hoses 1 21.53 KB 1 1
/gemmell/gallery/css/base.css.default 1 6.63 KB 1
/gemmell/gallery/tmp/vray-plugin-for-rhino-serial-number.html 1 17.25 KB 1 1
Others 6 16.67 KB 4 2

The number three most visited page on my domain is “gallery/tmp/download-freeware-.pps-to-.exe.html”. That is,  someone has used an exploit for Gallery V1 (or maybe just my mismanagement) and is using my site to host their illegal goodies. I’ve since deleted all traces of Gallery v1 and am hoping Gallery v2 is more robust. However, if I’d had more than say 100 people viewing legitimate things on this site, those hack entries wouldn’t have made it into the list and I’d have been none the wiser. Finally, I have found a good reason to be unpopular.

Aquaponics Revisited

Aquaponics - No Comments » - Posted on October, 23, 2007 at 9:42 pm

A couple of months ago I posted a progress report on my aquaponics…. well… actually I wrote it up and then FAILED to post it. So here it is. The data in this is a month or two old, but I did get several harvests from my aquaponics before it all fell to peices. Don’t worry, version 2 will be bigger and more robust. Anyway, on with the original post:

So you remember me talking about aquaponics? Well I’m not all talk you know. I have actually set something up and it’s been going for around 7 weeks. See my thread on backyardaquaponics (which is where I spend my time these days) and scroll down to the photos.

The jist of it is

Week 5

Week 7:

I’m starting to see some growth! I read an article that said that it takes a full year before a system is mature and working at full capacity, so should be some more good growth to come.

A Most Horrid Dream

Dreams, Ponderings - 2 Comments » - Posted on October, 8, 2007 at 8:46 pm

On Saturday night I had probably the most vivid, realistic, and horrible dream I have ever had in my life.

I was holidaying somewhere on the bank of a river with my beautiful girlfriend Ele (pictured here). Ele We’d parked the car right up on the waters edge. I was still in the car and she was approaching the waters edge. I noticed an alligator (it was definatley an alligator, not a crocodile) right where she was heading and I flicked a towel at it (?) and screamed at her to jump in the car. The alligator launched out of the water but she scrambled into the car and we were safe.

But then the sand underneath the front wheels started giving way and the car slipped into the water and started to sink. I climbed into the back seat and I said “ok on three we’ll jump through the back window, one…two…three” – blam I jumped out through the back window and landed on the sand.

But then I realised that Ele hadn’t come with me. I looked back at the car as it sunk below the water’s surface, and I started to panic; I thought “I should dive into the water and find her” but then there was hesitation “It’s alligator infested!” and then all of a sudden it was too late. I ran and told a life guard what had happened and then the dream seemed to fast forward to me sitting in the life guard tower with my head in my hands waiting for any news on the search. This part of the dream stretched out forever. The torment was immense – I kept thinking “I should have grabbed her when we jumped out, I should have gone back in to get her”. I was feeling hope, worry, and anxiousness. But as the hours dragged by these feelings were replaced with guilt, remorse, despair, the most gut wrenching grief and the unnerving realisation that I was now alone in this life.

Then I was sobbing into someones arms, telling them I knew she was dead, that there was no way that they would find her alive. And as I was doing so the search party returned, and they had something with them… I ran out to look, it was Ele’s torn up dead body, all white and dirty with sticks and muck through her hair – and that was when I woke up.

I re-lived the dream in that semi-concious moment just after waking up as I was taking a leak. As I returned to bed the whole thing overwhelmed me and I bawled my eyes out. It was so realistic, and I could still feel those strong emotions that I had felt in the life guard tower deep in my stomach. In those initial few minutes I felt a sense of grief and loss that I don’t think I have experienced before.

I then had a most surreal morning being comforted and consoled by the very person I was mourning. It was a really strange feeling, I felt as if she were dead, and yet here she was. It was almost the opposite of Lucid Dreaming (where you realise you are asleep and take control of the dream) because I woke up and thought that my dream was reality and this was something else. It truly was a most horrible dream, and it showed me a few things:

  1. Never park the car right on the waters edge, you never know when Alligators will strike (heh), or the sand will give out.
  2. Always attempt to save your loved one, make sure they get out or at least go back for them. The torment of not doing so is far too greater burden to bear.

Peace out.

PMD (Post Movie Depression)

Ponderings, Technology - 4 Comments » - Posted on August, 15, 2007 at 10:24 pm

Whenever I go and see a movie with some great hero who defeats all evil in the name of good I leave it feeling utterly depressed.

At the time I love it – we’ve just seen Harry Potter Order of the Phoenix, and whilst it’s nothing on the book it was a decent flick. However, as soon as the credits roll I start to feel glum and un-special. I’m no Harry Potter, the magical Hogwarts doesn’t exist, and really I’ve got nothing at all which sets me apart from the rest of the rabble we call humanity.

I get this feeling every time I watch a movie. It’s like some reaction to seeing greatness. All of a sudden I realise that I’m not doing shit, that I’m just living my life and that I’m not actually making an impact on the world. I start thinking up how cool it would be to build a castle up on some mountain somewhere and open it up as a school for technical wizards. We can teach bright young wizards (aka nerds/dweebs/geeks) how to wrangle the magics of computer wizardry. We could have transfiguration classes which focus on types and polymorphism, defence against the dark arts classes which focus on secure networking, and a virtual world in which magic (i.e. computer skills) are put to the test via duels and CPUidditch (a peculiar game where two teams attempting to guide worms and virus’ into their opponent’s network)….

See I know I’ve got a wicked (as in good) imagination, and I really feel like I should be able to use it somehow. However I can not write (as you can tell) and I can not draw/paint/sculpt etc. I can code, and a little imagination goes a long way when solving problems, but I’m no genius there. Poetry is fun but I don’t have the word-smithing skills needed for that either. I feel like I have a gift, but I’m not using it. And obviously I have deep seated delusions of grandeur which are exposed and raw after I watch a movie.

The real reason for the silence

Weather - 1 Comment » - Posted on June, 27, 2007 at 5:12 pm

I keep assuring you that I have actual content to post up here. And I swear I do…so my excuse for not doing so may seem a little…..well….lame.

See the truth is, it’s too cold to blog.

My computer sits upstairs in a large un-insulated room (a loft really) and I work during the day. When I get home, it is so damn cold in the room that I don’t want to spend any time in there. I’d rather snuggle up in bed with a Douglas Adams book. On weekends I am madly trying to get my aquaponics set up going so that I can start growing things, so I don’t get time to post then either.

As for the content: I have a really interesting/scary story to tell about just how much google can work out about you based on your website. But you’re going to have to wait.

Been Busy

Uncategorized - No Comments » - Posted on June, 6, 2007 at 6:32 pm

I am not dead, I’ve been busy. There is a lot going on in my life right now and blogging has fallen to one of the lower echelons in my own little “hierarchy of needs”.

I haven’t kept to my word and attempted lucid dreaming, I was meaning to post more on DBC (I will probably make it a permanent page as I think it’s the best thing since the devil invented defects), and I’ve been meaning to do a whole bunch of other things but I haven’t. Sit tight.

Unfortunately, I don’t want to tell you all what I’ve been doing since it’s been proven that it is goddamn easy to track me down already; I’m a little paranoid (but am I paranoid enough?) about how well a person can know me without me knowing…

The Problem with Software Quality

Software - No Comments » - Posted on May, 9, 2007 at 6:38 pm

For those who arn’t in the Software business, now’s probably a good time to go to another website. For those that are, I’m going to have a rant about Software Quality.

We are far too familiar with term “crash” than we should be. I pride myself on creating good quality software (and my job requires that I do since I work with safety critical systems). But the amount of crap out there is just phenomenal.

I was talking to a friend of mine who was about to roll out a software product at a customer site and I asked him:

“Is it well tested? Are you confident?”

He replied with:

“No and No”

Where I work we use DBC (Design By Contract) and find it immensely useful for finding defects. Basically we have functions like this:

bool AddItem(ListItem* item)
REQUIRE(item != NULL);
//add the item
ENSURE(list.size() > 0);
//return result;

If a REQUIRE or ENSURE is ever violated an onAssert__ function is called with a file name and line number.

This means that I can write a function and be damned sure that if it’s ever used in a way that wasn’t intended we’ll know straight away. See the problem is generally that a fault in code occurs, say something returns a 0, and then sometime later that value causes the application to crash. Unfortunately this may be 30 function calls later leaving you with a stack dump nowhere near your original problem. In my experience DBC allows you to catch the error when it occurs, and thus saves you time. If you use it, you’ll find that you get a DBC error and think “Thank god for DBC, that would have been a bitch to find otherwise”.

Anyway, I digress. I asked him whether he’d like our implementation of DBC and he said “nah, it’d be impossible to institute here anyway” and then he listed a two main reasons:

  • There is no emphasis on quality. In his line of work time to market is way more important than correctness and quality (which I find hard to fathom). So it doesn’t matter if you deliver a wrong product thats full of bugs, just so long as you’ve delivered something.
  • There is general apathy for quality in the workplace. People don’t want to improve things. They’re happy hacking away and since there is no requirement from above, why would they want to change?

Why don’t people want to improve the quality of their code? Because:

quality == boredom.

Code reviews/inspections are by far the most efficient method of finding defects (see any of Humphreys texts), but I find reviewing someones code horrendously laborious and boring. Software is notorious for having out of date or non-existent designs, why? Because documentation is boring. Testing? Boooorrrrrring. Coding however is lots of fun! Thats why I became a Software Engineer. Thats why we have a thriving open source community. Thats why there is so many really bad quality products out there.

The problem with Software Quality is that it is not FUN. I don’t know if it can be fixed, but thats the way I see it.

A Simple Search

Security - No Comments » - Posted on April, 23, 2007 at 8:59 pm

So I was at work about 9am the other morning and the work phone rings. I can tell from the ring tone that it’s an external call. I pick up and some guy says “Hey, my name is <something something>” (I didn’t catch his name) “I read your article about Peugeot 306 cabriolet hoses on What diameter are the hoses you use in that article?”

More than a little taken aback I say “it’s called speed flow, and I think there is only one size……. how the hell did you get this number?”

How to stalk Simon Gemmell?

“It was pretty easy” he says, “You mention that you work with Radars on your “about” page. You also mention the suburb where you work in one of your blog posts. A quick search for Radars in that suburb brings up your company name, I ring the front desk and ask for a Simon Gemmell and they put me through”.

Goddamn. It was THAT easy? Two little facts like that? I work with Radars and the suburb I work in? He could have emailed me, but I bet it was harder to work out what my email address was than track me down and call me!

The guy wasn’t a psycho or anything, he seemed quite reasonable and he gave me a tip for fixing the windows if they ever break, but it certainly was a shock. I suppose somebody who finds my wallet on the street will probably have more information on me, but it’s just the ease of tracking me down that scares me. I will be careful about what I post (and have in fact edited some details in previous posts).

Goals, Dreams, Needs and Lucid Dreams

Ponderings - 3 Comments » - Posted on April, 14, 2007 at 9:55 pm

I think there is a an important distinction between a goal and a dream. A goal has some achievable outcome and a deadline. A dream is something less substantial and it’s something you will probably never actualise. As I said in my previous post, setting too many goals can be dangerous to your general well being because you end up chasing your goals. But you can’t really chase a dream, it’s always so much further away than a goal, and it’s so hard to grasp what you actually want from it so I don’t think it’s such a problem. I get a warm fuzzy feeling when dreaming, but I don’t get the same nice feeling when I think about my upcoming goal. I think having dreams is important, because dreams give hope. And hope is essential to feel human. Or maybe I should say something quotable like “to be human is to hope”?

I think my darkest moments have been filled with a distinct feeling of complete hopelessness, which correlated highly with a complete lack of will to live. Not as in “I want to die”, but “live” as in to get up, move around, do something proactive, achieve etc etc.

I’m no great thinker, here are some quotes from some people more eloquent than I (source):

  • To eat bread without hope is still slowly to starve to death. (Pearl S. Buck)
  • He who has never hoped can never despair. (George Bernard Shaw)
  • Hope is the worst of evils, for it prolongs the torments of man. (Friedrich Nietzsche)
  • A sobering thought: what if, at this very moment, I am living up to my full potential? (Jane Wagner)

Anyway, my original intention with this post was to bring to your attention the Maslow Hierarchy of Needs, and discuss whether it relates at all to the general well being of the person. See I think you can reach the top of the pyramid, self actualisation, and still be terribly unhappy. In fact, I don’t think it addresses well being at all. What DOES it address? Anyway, those down the bottom have some simple needs, and I’d say they have a lot of hope. I’m not saying the beggar is happier than the aristocrat, but those at the top may have everything except hope, and hence feel completely lifeless, where as the beggar feels hungry but alive. Hope is necessary but not sufficient for happiness.

The other thing I wanted to bring your attention to was this really interesting article on lucid dreams. This ties in with both the “dream” theme of this post (although it relates to sleep dreams as opposed to life dreams) and the Maslow Hierarchy of Needs. Basically it says that you can have some level of control your dreams and actually use them as a tool. The lucid dreams FAQ briefly mentioned being able to use it to achieve “self actualisation”. Certainly an interesting article anyway and it related to what I was thinking about at the time.

Since the FAQ said there is not harm in attempting to enter into lucid dreams, I’m going to try it out. Getting the “rush” of knowing I’m in a dream sounds like fun to me. I’ll let you know how I go. Then you can brand me as a new age hippy and be done with me. I’m not a hippy, I’ve just got an open mind (maaan).