Backyard Aquaponics
A place to discuss aquaponics

Just a note on using passive return as airaetion.

up until a few days ago my system returned water via a 50mm DWV pipe about 20cms above the water surfave, it was a relativly gentle flow out of the tube, that was laminar, bearly breaking the waters surface.

After a failed flood and drain attempt the return now has an end cap on it with a 15mm pvc elbow pointing down. I could swear the flow was double, but i know that its exactly the same, point is, its now turbulant and under pressure, making much more splashing and although i can't measure the O2, i KNOW its adding HEAPS more than before. same flow, different outlet setup.

This is how I have mine Steve. I should have introduced the PVC elbow water return as an 'improved aquaponics invention' on the new inventors.

LOL, might have even got a 40K grant for it

Nah, not complicated enough, needs an inbuilt solar powered monitoring chip with variable flow control Then you'll get your 40K

E2

Thanks for the further details EKB and 'Murray' (I’ll spell you name right this time ). There is a lot to consider, and I can't be sure (can I?) whether the system will have enough O2 added to replace what the fish use until they are using it!

Has anyone tried the use a solar powered aerator?
How many people have additional aerators rather than just relying on the normal flow of water through the system?

Sorry if I'm off track...

Astis,
I have a backup system which is an old 14 cfm compressor that has a pipe going to the bottom of the fish tank bubbling away. (I changed the oil in the compressor for some olive oil just in case some oil came through with the air, although not likely as I have a good quality air filter and water/oil trap)

It will provide air for about 4 hours if the power goes down or if the system stops circulating which it does every 3rd or 4th day due to needing a water top up of 10 or 12 litres...
VB Has a backup system that works well also involving a fail safe relay and a 12 volt water pump that comes on and creates a waterfall if the power goes out. VB has posted details of that somewhere on this Forum.
Muzza

I have a four line aireator running 2 air stones in each tank and pump buypass also in each tank how do you measure disolved oxy

Thanks again Murray. Both options sound good, I'll see if I can find VB's post for further details.

F&F, there are a couple of scientific ways, involving DO meters ($$$$$) or chemical testing (complicated). There is of course the other way, if your fish are gulping at the surface...

Here's the link: VB's backup system

Muzza your coco peat grow bed is it attached to the sytem (ie water flows back to fishies. Or is it and on its own type set up. If it is attached what kinda of water quality do you get from it (ie dirty etc)

JT

jtjf_1,
The coco peat is hooked into the rest of the system and it has sent the water very, very, very brown, just like a very, very, very strong cup of tea. The dozen Jades I have left swimming around in the water are happy. I have come to the conclusion that Jade perch are happier in discoloured water, they do not get spooked at all and they just go about their business.
I admit it is nice to be able to see the fish, but it does not matter really. I am letting the system run as is, to see if the coco peat discolouration gradually goes away....only a month or so of being part of the system will tell me that, but I have established that the coco peat does not harm the fish in anyway. The plants really like it, it retains moisture really well, but drains beautifully.
Muzza

I probably wouldn't worry too much about the colour either, but I wonder if it might be tainting the flesh of the fish (re: taste).

VB, If I could just keep some fish long enough to get big enough to eat I would't mind if it tasted like coconut.
Muzza

True :-).