Backyard Aquaponics
A place to discuss aquaponics

Just for the record, Western Rock Lobster (like Southern Rock Lobster) is their real name - crayfish is the local name.

Michael F......when you speak about crayfish are you referring to a freshwater crustacean or a saltwater one? The Rock Lobster lives in saltwater (usually very clean saltwater) whereas our freshwater crayfish are known locally as yabbies, redclaw or marron (each one a separate species).

Cheers... Aha, you haven't read my other post. I ordered my rainwater tank from EB's guy today..

S77,
How are your syphons on the grow beds still going, presumably the same as when you put them in?

Also where did you get the flexible hose from, I think I read somewhere you may have got it from a hydroponics shop.

Cheers
FJ

That sounds like an awesome idea!!!!!

you could harvest the claws and have like a marron claw morney, or marinated and BBQed or use them however. Then if they are anything like yabbies they will grow their claws back and you can repeat it.

Then again it may hinder their feeding.....im not sure (and then the pain? see below)

and while fish /animals might not have the same socail set up as us as far as housing density, i'm fairly sure pain = pain

It would be cruel IMO + while they are tasty, I'm not sure it would really be a reasonable reward for effort.

Sounds like a candidate for that show on Discovery, "Dirty Jobs".... Marron De-Clawing. The host Mike Rowe discovers that thick leather gloves are a must....

Hey FJ, sorry for the late reply. Missed your post in there... Theres so much to read I forgot to check my own thread.

The siphons haven't missed a beat at all, The beauty of the flexible hose is that it lets you set up a nice smooth loop. In my setups I have found that if you include any hard bends in the piping, at any point in the pipe, it lowers the maximum flow rate due to turbulence and therefore inhibits the initiation of the siphon (it starts later). I did have 90deg bends in some of them but would have issues with the siphons initiating sometimes. The growbeds would overflow and they took longer to drain.

I got it from a place called Aquaponics, on Warton Road, Canning Vale. 13mm rubber "Raintube" $2 pm, but worth its weight in gold for setting up the siphons in my small systems.

I have my digi camera on charge now, will post a couple of pics later including detail of the siphons for the other person who was asking about them.

In my limited experience with auto siphons lately I found similar problems/outcomes! - which means makeing allowences for the slightly higher water levels before the siphon starts to work effectively

OK, for easyihzy, my siphons explained a little better.

Materials:

PVC piping - 90mm stormwater works for me, can just fit my hand down into it.
13mm Rubber "raintube" - nice and easy to bend, but 13mm garden hose works just as well and is cheaper, a tip is to find non-barbed fittings (elbows, tees etc) as they are very hard to get off when used with garden hose. Other diameter tubing will work also, 13mm is the easiest to get fittings for and works well for small systems like mine.
Cable ties or string.


Method:

1 - Make a standpipe. Cut the PVC pipe to a length roughly the same as the depth of your growbeds. Drill holes that are smaller than your growing media and one hole near the bottom that is large enough to accomodate your drain tube (siphon).
2 - Drill a hole for your drainage tube into the front of the growbed, at the same height to match the hole in your standpipe.
3 - Insert the siphon tubing and make a smooth loop in the tubing (which you can secure with string or a cable tie), ensure that you cut the end of the siphon at a point lower than the bottom of the growbed. Fasten the top of the siphon to the lip of the growbed initially with string, you will need to fine tune the height of the flood, you do this by changing the height of the top of the siphon loop.



4 - Fill with your media. The size/shape of the media will determine the amount of water displaced by it, this affects the rate of fill of your growbeds, and hence your siphons. You can test that the siphon works in an empty growbed, but its behaviour and flood and drain times will be different once it is full of your growing medium (if you are using one ).




5 - Set up your pump, and plumb to your growbed(s) and ensure that you have a valve on the outlet for each of the growbeds so that you can alter the fill rate of the beds. FYI, my beds fill at roughly 2L per minute.
6 - Start your pump and watch the growbeds fill, and hopefully, initiate siphon somewhere round the level that corresponds to the height of the top of your siphon loop. Ideally, this will be just below (2-5cm) the surface of your media. The pics below show the level at the top of the flood, indicated by the discolouration of the pvc standpipe....

... and the siphon, the top level of the loop is as high as the water level gets in my system.


7 - If you need the bed to fill more, raise the siphon loop, less, lower. Easy...
8 - Now, you want the flood and drain cycle to happen automatically so you can have your pump running continuously but the beds to keep cycling, flooding and draining again and again... what we have coined an auto-siphon.
This means that your drain rate needs to be faster than your fill rate, in my instance I am getting a drain rate of 6L per minute. I think LKB is working out some of the maths, and I'm sure a piping engineer could help us out here as well. Anyone know one?
I have found in my experimentations with these things that the smoother the path in the pipe, the less turbulence is experienced and you get a faster drain rate. And the faster the drain rate into your pond, the more aeration and hence, happier fishies.
If you find that one bed is reaching siphon and then never fully draining, we call that a leaky siphon. The siphon leaks at the same rate as the bed is filled and the water level never rises sufficiently to reach the plant's roots. That's why we put the valves onto each of the growbeds. You can slow the rate of inflow into the bed with the valve slightly, and try again until the bed drains to the point where the siphon sucks air, the siphon is broken, and the growbeds start to flood again.

Notice how point 8 was the longest one - thats because it can take a little tinkering to get it right, but trust me, once you have it working they are almost bulletproof. You just need to make sure no dross gets into the standpipes to block them up and they will work reliably all the time, everytime .

Despite the long winded explanation, these are really simple to setup and are cheap too. Make sure you check out LKB's posts, and others as there are numerous designs for siphons that overcome issues such as trickle rate inflow etc etc.

Simmo, what a hero!

We were just discussing last night the different methods needed for draining all the different grow beds. Loopy siphons were decided on for the blue drums (20 halves) and now you've just given me an instruction list! Yay!

looking great simmo,

i can't wait to see what you do with the fibreglass tanks when theyre ready. any thoughts yet on how they are going to be used?

nice work.

Cheers guys, not exactly sure what I will do with my (hopefully) 2 tanks from you BF, have a rough idea and might have to start digging a trench to put down some electrical conduit out the back. You have to put that down at least 600mm right?

I'm also wondering if I need to get serious with one of Murray's pumps etc. hmmmm.

and yeah, I reckon this design would work perfectly for your blue drums Jaymie.

hi simmo77, 3 cheers for your effort and lengthy explaination of your system, it really clear a lot of doubts regarding the height of the siphon tube and the upturned U designed. thanks

btw are the medium in your grow bed called "hydroton" or it is other generic clay balls?

NP mate. Yep, a mix of hydroton and what we call pea gravel, or scoria.

I dont want to take a sale away from Murray - I am always eager to help members - but consider your next step/system more carefully than I did before purchasing one of the 'workhorse' pumps he has...
as I look at my system now I realise that I have WAY too much pumping power (which will be choaked back and diverted as well)... I know that I will be able to add another 4 bath tub grow beds with the pump I have

Oh yeah, great job on the auto siphon post - thank you for that!