Backyard Aquaponics
A place to discuss aquaponics

Gabe, yes thats the immediate temporary plan, I have a fair bit of 25mm rural poly that I'll borrow for the task.
I'll put it on the ground nearby and circulate water through it and the Pex-Al-Pex pipe around the outside of the FT for now, until I can afford to set up a much more efficient and effective evacuated tube system with storage + wax for extra capacity.
Water temp was 11.9 when I measured at 17:00, but will be lower by now as the air temp has been in the 5s the past few hours, with drizzle.

The FT water was at 8.9C @9am, after a miniumum of 2.7C with a light frost this morning. I've uncovered the sump to catch a few warming sunbeams, but it is clouding up again now I've cut the night time water pumping duty cycle back to 5 or 10 mins in the hour, to reduce the overnight cooling a bit, and might cut it back a bit more I thnk.

The Murray Cod have gone off their food, and I saw one in the ST looking pretty lethargic, but it managed to escape my attempt to net it to return it to the FT. The others in the ST seemed lively enough though.

It must be time for an update... I haven't set up any sort of heating yet, other than uncovering the ST on sunny days to absorb a few rays from the sun, and temps have not been as low as early May when I had a couple of frosts. Afternoon max water temps have been in the range of 14 - 18C, with mins a few deg below that, based on past experience, since I haven't been measuring in the mornings recently. The Murray Cod aren't eating much, and still are not interested in pellets, which I have to regulalrly scoop out of the ST. I bought a 20kg bag of 2mm starter semi-sinking pellets from Ridleys, and mix a few grams in when I feed Blood Worms or my home made mix, but most, if not all the pellets end up in the ST.

I've restricted the SLO with only small holes so I'm not getting any fish in the ST these days. I did lose a few in there, stuck under the pump, and I had 3 deaths in the FT over a few weeks too, no real idea why they died, other than perhaps they were injured when caught in the net in the ST for removal, but I've have had no deaths in a few weeks.

They aren't eating enough to cause much acidification, so I haven't been adding much KOH for some time, but did add a little of the human P element a few times to give the bacteria something to do. Otherwise I'm adding Blood and Bone and Seasol every week or 2, as some of the tomato leaves appear to be a bit deficient in K and P. They are still popping out flowers which form fruit, but Ive been pruning them off, just leaving the larger fruit, which is slowly ripening. There are some nice sized tomatoes on there that I'm reluctant to give up on, but will have to sacrifice them if they aren't ripe in the next couple of weeks, so I can plant some other winter crops. I did prune them right back to remove most branches and leaves, just leaving those with fruit. I've picked over 154kg from the 8 plants now, since xmas.

Some disturbing cracks appeared in the ground near my outside GB #9, so I moved it in from the edge by 40cm. It is all on fill from the holes I dug for the FT and ST, and a fair bit of rain had softened it significantly. Moving the full GB was an interesting excercise, but went smoothly with the help of my FIL. I took action before anything disasterous occurred!

One delicious vegetable has been the Peruvian Ground Apple or Earth Apple, which produces tubers with a texture like carrots, and a taste between carrots and apples- crisp and only slightly sweet. It is incredibly versatile though- I had some the other day diced with ice cream, and later on had some sliced with home made cheese and AP tomatoes on top. Dee-lishus! My MIL used some in a potato bake, and I've put them in soup. I'll be keeping some small tubers to plant in spring. That also had nice yellow flowers.


Tha cauliflowers have been growing well too, here is the groth over the past 10 days





I've picked one pumpkin, which was in the ground near the AP system, and partially watered with AP water, and there are 2 more large pumpkins and a few smaller ones still growing. I'll leave them until after I've had a few more frosts, as the vines are still looking ok.

I've cut the night time water pumping back to 5 mins or less per hour for most of the night, to reduce heat loss. The ST is covered all the time, except for sunny days. There has been no hint of any pea soup forming.

I've also been buying components for the back-up system, which will be solar powered DC only. A Sun Sun 12V 50lpm air pump and a 24V RLSS WaveLine DC-6000 Pump will do the work. They will be powered by a 24V battery made up of 2 X Staunchcell 12V 55AH gel batteries, and the 12V supply for the air pump will be delivered by a Meanwell 100W 24VDC to 12VDC converter. Energy will be provided by 2 X 220W PV panels, arranged to deliver even output throughout the day, not a peak around solar noon. I'll run a completey independent water delivery system to the GBs, to avoid the use of one way valves, which I found tended to not close properly due to algal accumulation in previous tests with parallel 230V pumps.

To start I'll probably alternate use of the backup and main system with timers, so that if one fails there is still half the pumping action happening due to the other, but may eventually try running from the "backup system" most of the time, with the main system, which is also solar powered from the house supply, as the backup, for at least some of the time. I'll just have to see how reliable the 12V and 24V components are.

Good to hear from you Gordon. I second you with those Peruvian ground apples although I grow mine in the soil garden. They're high in inulin which is great for diabetics (and everyone really). Well done.

Looking quite good!

My Cod are getting off their food a little too. How big are yours now?

I'm curious about these Peruvian Ground Apples now. I want to try some.

Where did you get your seeds from?

you buy tubers
i.e. http://www.greenharvest.com.au/Plants/I ... Yacon.html

The dead M Cod a few weeks ago were around 10g and 10cm, nowhere near as big as the beast from the bung hole that bit off more than it could chew, a while back. However, there are still some very small ones about 5cm long too. I'm sure some of the smallest ones have been eaten, as their numbers appear to be down on what they were.

I got the PGA tuber, aka Yacon, from a friend. You usually grow them from the tuber, as with potatoes, but I cant see why they wouldn't grow from seed. I'll see if I can find some in the few remaining flowers on the 3rd and last one left in the AP. This morning I had some PGA chopped on my museli, along with home made yoghurt, preserved apricots and soy milk

Update on the trout, eating that is
In the mad rush to get them processed in the December heat, I neglected to remove the spinal column blood from the first few bags I froze. We've eaten them as we came across them in the freezer, and they've all tasted fine, and tonight I cooked the last bag of 3 of those trout. I can only say they were just as delicious as the ones we ate 6 months ago, we could not detect any deterioration in the flavour, so the blood had no detectable effect on the quality of the fish.
I have been running the chest freezer colder than absolutely necessary, as fish will last longer when kept at lower temps, and I think I've been below -25C the entire time, and below -30C for much of it.

How low a temperature can Murray Cod survive in? I'm not sure, but my system water was down to 7C this morning, and I didn't see any dead ones when I checked this arvo when it was up to 7.9C. The average temperature for the 24 hours to 9am (average of temp every minute for the 24 hours) was just over 4C, with a minimum this morning of -0.2C, so the buried tanks are helping keep the water temp up quite well. It was overcast most of the day, so not much solar energy gain.
The hailstorm, with stones up to 40mm, on the 28th only put a few small bruises on the pumpkins, and didn't put any obvious holes in the waterproof shade cloth over the 8 covered GBs.
The air temp was down to 4.4C by 6:15pm this evening, so I expect a cold night again tonight, but I'm hoping the sun will make an appearance tomorrow to add a bit of heat.

The best I could find is optimum range from 7C-24C. But mine survived at 31C for a short time.

See how they go. It's cold here too, but not as bad as you.

Are yours still eating?

They've eaten very little in recent weeks, but the water temp has been in the 9-13C range for about 3 weeks, dropping below that for the past couple of days. They still wont eat pellets, even though I throw a few in with the Blood Worms or the blended and frozen ox heart + pellet mix. I scrape them out of the ST every week or so.

Hey there, I bought some earth apple from greenharvest thanks for reminding me

How are your Cod going?

We had a very chilly night last night, and had two dead ones today

I've had 12 frosts this month, and there is already frost out there tonight at 8pm, so 13 now, so its been fairly cool here lately, but I haven't had any deaths recently. Daily max water temps have been as low as 7C, so minima probably as low as 5 or 6C, although I haven't been measuring the morning temps.
They aren't eating much, and still not eating pellets at all, so aren't really increasing in size as far as I can see.

How cold has your water been?

Only my first frost of the season. So slightly warmer than you.

First one of my larger cod that died. Probably the biggest one in there, and one of the smaller ones.

I was hoping it'd be the weather, rather than anything nasty happening. All my water reading are at 0.