Backyard Aquaponics
A place to discuss aquaponics

Another way Ive seen posted by Ryan is to use a pure oxygen cylinder. Run it through a normally open solenoid valve and a few air stones. Power goes off, valve opens - air supplied..... power on, valve closed. A full 'E' size cylinder will last approx 5 hours at 1 litre per minute. There is also a cool formula to work out how much time you have left using the pressure reading in the cylinder. Each size cylinder has a different factor that you need to use and you could prob find that chart on the net. I do remember E size cylinders use a factor of 0.28 so the formula is PSI x Factor / Flow Rate = Minutes of oxygen left. The flow rate number you use is in increments of litres per minute.

Example would be, say your E size cylinder has 1600psi left and your flow rate is 4 litres per minute.

a. Multiply 1600 (your Psi) by 0.28 (x factor for E cylinder) and you get: 448
b. Divide 448 by your flow rate: 4, and you get: 112
c. You have 112 minutes of oxygen left

so had 1 of my staff at my disposal today so took advantage by getting him to help me with the 7m roof sheets etc and sheeted the stables today. Misses is happy lol, and since they are now sheeted i can continue with the chook pen as it is positioned hard up against the wall of the stables.

Fair days work...

No rest for the wicked lol, got the chook pen sorted on Sat as 7 week old chicks arriving tomorrow, still have to put a dog proof fence around it though, will have to try and do it during the week although back to work this week damn it. Also picked up a new honey extractor and built a new bottom box with some under body beetle traps. Also fired up the still to make some essentials . Essential oils that is
Didnt get a chance to shift some fish over from Stage 1 to Stage 2, will have to try to get that done during the week also, along with the fence and removing the winter honey off my hive, damn i hope i get off early a few days this week.

Damn it i seem to be hooked line and sinker, just built a stand to carry the tub for the duck weed and got to be thinking that a floating raft system would look good in there and probably suit out 6 mouth strong salad munching habit better. I had no intentions on a floating raft system until today lol, but i cant see the current GB's keeping up with the hungry mouths.

So you are familiar with what i already have, i am planning strwberry towers for Stage 1 and i am working on them now, so duck weed bath/pond going onto stage 2, besides i have more room down that end of the green house, now for the questions lol.
Am i better off feeding duck weed pond from sump or straight off my SLO?? Both are easy for me.
The floating raft i imagine would be better off coming from the sump so basically the GBs are the solds removal, but how about sump to duck weed then to floating raft then back to sump?
I know i will be getting re-cycled water but with 4 GB's feeding the sump i think i should be right. I can also up the water flow to the GB's to make sure the cycling is at its max. The duck weed pond will also act as a pre filter.

Whats your thoughts??

Remember that with floating raft, you need additional aeration for it. About 1/2 CFM for every square meter (sorry I'm not sure how many liters per minute 1/2 cfm is.) I have gotten away with no additional aeration for some micro rafts I do but those are only able to successfully grow lettuce to about a baby lettuce stage for my living lettuce mix. If I leave the plants in there any longer than that they don't seem to thrive and I find I'm growing overpriced chicken treats then.

Thanks TCLynx, yes i intend to run an aerator in there, i will probably ask some questions about that later ie how to spread the air out etc once i get a little further into the build.

Does anyone have an opinion about the proposed feed??
My only worry is nutrient level or possibly lack of??

In my raft beds I usually just place 6" air stones every 4 feet in a 4 foot wide bed by 1 foot deep. The bubbles rise up and when they hit the raft they spread out (and actually help clean the plant roots a bit.)

Thanks TCLynx, i will do something similar for sure.

ooops double post so deleted 1

Chook pen taking shape, although my bloody dog is doing his best to get in to munch on some chooks
Thinking might have to get one of those training collars as he just isn't loosing interest and with his current persistence it will only be a matter of time before he gets a taste.

And my duck weed and DWC is coming along. Plan is to feed the DWC from 2 duck weed tanks although i only have 1 bath at this stage, still have to find 1 more freebie.

Do you have foxes around your place... they'll be over that fence and into the chooks before the dog...

P.S.... the dog is either a really well behaved dog... or he's got really short legs... if he can't jump the fence...

Lol wheres the faith, the chock pen is fully enclosed with a buried mesh perimeter for insurance, the attempts were made pre fence, the fence is just another barrier and to keep anything away during the day when chooks are out. Our intentions are to free range them once we get the stupid dog under control.
We have the odd fox here, they claimed a few chooks during the night in the past but it was a stray dog that wiped us out a few years back along with everyone else in the street, chickens, ducks and turkeys were all killed in the street in 1 week, a lot of pissed folks around but no one found/caught the culprit.

Will try Ruperts suggestion with the lights later and let you know what happens tomorrow.