Backyard Aquaponics
A place to discuss aquaponics

why are you trying to heat netab? to run warm water fish? could you just do the seasonal veggie/ fish thing, then you can put trout in

Just an obsurvation,

the Silver Perch at the nursery sill feed fairly well and the water temps are around 13c, fed them today and they went nuts on it.

they are between 80mm-200mm though

then theres the boss fish who is like 2.5lb

but they are growing like mad and still feeding well. can you winter them out and run some trout in another tank or two??

Abdul and Swanberg,
Ive read about their compost heating method a while back and love the idea of it... but like Swanberg said, that would take a LOT of compost and man hours to build up and maintain like Growing Power do!

Your probably right tho Abdul... Ive read that even having drums of water in the GH that warm up during the day then release it at night can help... so If you can do it right, using something that actually creates its own internal heat like compost is a pretty cool option...

I reckon one of the 'drum on a stand' composters that you can rotate with a crank handle would be easier (and quicker) than blue barrels tho... but would barrels be big enough to work for hot composting?
looking at it from a commercial viewpoint, the easy answers are... to see if it can be done? - no, to keep growth rates of native fish like perch and cod consistent and strong over winter, and - Would love to try trout, but for a large scale system up here I dont know if they will be a viable option, if nothing else due to the fact that our nearest supplier is so far away, so there would ultimately be very large transport costs involved, and when wholesale trout prices are fairly low, they may not be viable even with the quick turnaround (I would need to do more research and costing on that one down the track).

Also at the volumes we would be looking at they would be very risky to produce in this area... too many heatwaves and unseasonal weather conditions, and to me, its easier to tweak the water a little warmer, than trying to drop it by 10 deg without using industrial chillers that would cost thousands to run... Theres a big difference between experimenting with 100 fish compared to 10,000... But then again, trout may end up being an option (even our only option), but we would like to see what we can achieve first.

Whether its this winter or next one (we are running out of time now though as our packing season starts on Wednesday) we would like to find a method that works, and can be increased in size to economically heat a big system to continue growth rates. And ultimately, thats our main priority for this system... to prep us for our big one

When looking at Aquaculture systems, growth rates need to continue year round to make the business viable, but the equipment used for heating is big and power hungry... We want to find a low cost, efficient system, as well as finding one thats as sustainable as we can get... so if we can find something that works, we can then start modifying it. If the gas heater or wood fired heat is a viable option (and Ive also been looking at Bio Mass Generators which are really interesting as they can produce power as well as clean heat) ... then we can start working out a way to make it more efficient and stable.

Ours were 80-100mm when we bought them, and the temps are around 16-17c ATM and the silvers are still feeding well.

To be honest we will be wintering them anyway... no choice now as our citrus season is starting earlier than we had anticipated... and we are curious as to how low our temps get, and how the system goes.


We were just wanting to try our mates spa heater because he offered to bring it around , but also we were all just curious to see if it would work... and if it did, then I could keep my eye out before next winter for one of our very own ... even if I found one next week, unfortunately we just wouldnt have time to make the modifications before the end of packing season anyway which by the look of things wont be until summer!

The other option was incorporating water heating pipes or tanks hooked up to a pizza or earth oven, and we were looking at that because I would REALLY love one anyway before the fish are edible

I was given over 100 Grass Roots mags about 10 years ago, and one of them had an article about a wonderful backyard oven made from stone which consisted of a fire box which heated water in a receptacle large enough for 1 person to sit up to their neck (imagine tall, but narrow in diameter with a small stone bench to sit on) and also an oven which apparently cooked wonderful roasts and breads. The bath had taps connected so that cold water could be added when it got too hot to bathe in, and hot water taken out. So ever since I read that Ive been interested in outdoor ovens and their potential for heating water (and were originally looking at building our own spa system with it)... and just reckon it would be wonderful to incorporate into the system if we could

On a lighter note... we had a lovely day yesterday when Mantis and his family came to visit!

Thanks so much for coming to see us guys, it was an absolute pleasure to meet you... We hope you enjoyed yesterday as much as we did

And thanks too for giving Hubby a chance to sample your homebrew Mantis He was REALLY impressed by it, and is definitely a homebrew convert now I think!

Iv been looking into making a stainless heating coil, my mate has Rollers and we can get the pipe, would be interesting to see how it would work, it would be very easy to overheat a small system, however a large system would have some more play. i was just going to make a small firebox and have the coil welded to the back of it. this would be to heat 2kl in my shed for silver grow out.

Richard is a top bloke ay?? we have caught up a few times must be my turn to head over there soon!!!

Yup, he is a really great bloke... would love to have spent more time catching up actually, but am definitely not complaining ... Hubby and I are still really chuffed to meet a fellow BYAPer... and its pretty interesting being able to have chats about the forum and everything else...

Jamey, you are more than welcome to come over ANY time... we would love it... just keep in mind that Mantis has set the bar very high ...

Either that, or if we havent seen you by the end of packing season, we may just have to make a trip down south and do some BYAPer visiting ourselves

Love the heating coil idea. One suggestion our spa/engineering mate had was instead of trying to incorporate stainless coils into an earth oven, have a stainless tank behind the fire with an insulating divider between them and extending the depth of the oven (looking at around the size of a toilet cistern for the stainless tank from what he suggested)... and have an in and out line. He thought it would be more stable than coils, and easier to manipulate temps

How are you thinking of running the water into the FTs? Would you run it into a mixing tank first?

Definitely keep us updated... if it works it will be awesome!



Sorry if that big speel seems a little from left field a couple of posts back, and hope you all understand where i was coming from with that one

Because commercial is what we would like to do in future and are discussing it between ourselves, its what I tend to have in my head all the time... if I try this, or if I do it that way, how will it convert to commercial... blah blah blah.

anyway...

Yesterdays water tests:
Amm - between .25 and .5
Ni - 0
Na - 0
Ph - 7.6
Temp @ 7am - 17 deg
Temp @ 10am - 16.5!

So our pH might be starting to drop which is good
... also looks like the GH is already starting to cool the water temps when we turn the system on in the morning...

Got another 100 yabbies dropped off to us last night from the fellow with the dam, so will have to see how this lot go as we lost most of the other 300... we thought it may have been from a huge pH difference as our water is so alkaline, but it could have been the fact that they were held for too long before we got them, so fingers are crossed.

Is there any reason why you turn it if overnight netab?? That will reduce tour potential stocking levels ...

Yeah, but at the moment we really need to... I think I was talking about it a while back...

we are still having overflow problems with the 2 tier beds due to the mesh screens blocking, so we are trying to save water, plus we dont want to wake up to fish sitting in the bottom of the tanks ... so until we add the new tanks to stabilise the water levels a little more, and change all the duckweed tanks to gravel GBs, and considering that we arent planning to get any more fish till after winter anyway, we figure thats the best we can do for now.

It was great to catch up with you guys yesterday and get a tour of your fantastic system and the fruit shed, amazing stuff. By the look of the loaded fruit trees you are going to be busy this year.
I was feeling no pain on the way home (wife driving) after the beers flowed freely

I think Hubby was still feeling pretty painless by lunchtime to be honest
He really enjoyed your beautiful beers and was so chuffed that you brought some up for him, so thank you for that... very much appreciated

and regarding the loaded fruit trees.... please dont remind me ... going to be one of our biggest years, as the crop is one of the biggest in history for this area... so will be very busy over the next 6-8 months trying to get through it all

Anyway, it was a perfect excuse to forget about all that, and talk about our favourite subject with someone who loves it as much as us ... (unlike family and friends who are getting pretty bored with our only conversation starter nowadays )

Will see you again tomorrow when you pick up the trailer on your way home... looking forward to another chat if you have time

Cheers

het netab any updates???

Hey FB... thanks for asking

Not much really... been trying the last few days to get the salt ppt up as our silver perch are flashing pretty badly.

was at 1 ppt a couple of days ago... but after 2x25kg bags of salt its now just below 5 ppt.

Chillidude had suggested bumping it up to 6 so we'll see how its sitting tomorrow morning and might add a bit more...

5ppt should stop them flashing IMO, but you may as well harvest the cucumbers cause they may not like it.

Yep... cucumbers don't like much above 3ppt... and strawberries not much above 2ppt...