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.


  1. Did you use local worms or specifically composting worms (like the European Red Wiggler)

  2. I bought mine as fishing bait, but they are definitely composting worms, and not earth worms.

    As I understand it, composting worms like to hang out near the surface, and earthworms go deeper and eat different stuff.

  3. You fabricated pond yourself to make common habitat on your ranch house. There are numerous component of pond. It keeps balance in biodiversity. Govt. should not have any issue by your pond. Read More


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