Backyard Aquaponics
A place to discuss aquaponics

I think most people in Melbourne are frustrated that we can only grow trout for 9-10 months of the year. Also it's far to cold for 6 months of the year to produce the warm species. Silvers seem to be able to handle the cold but do not feed during the winter months and if not big enough they will not make it through the winter.
Well first I would like to say that this idea is not my own, and got the idea reading it on Dicko's system thread. (I'm sure there is others that have toyed with the idea.)
Being a refrigeration mechanic I though that I could build a system that was capable of keeping trout over the summer months.
To design a system was going to cost thousands $$$, so I though I could pull apart some small freezers and lay the evaporators (cold part) flat on the bottom of a fridge panel tank and cover with pond liner. I think this still this would of worked well but very labour intensive because you still have to build insulated GB's & sumps. I still think this would cost well over 2 G's to build...
To reduce the labour and remove the engineering side of thing out of it I decided to investigate purchasing Chest Freezers which can be easily sealed and suported.

So I thought I'll put up my plans for your viewing pleasure/comments

Design.
System to CHIFT-PIST (Can not go wrong with this design IMO)
1000L FT (Chest freezer)
650L GB (Chest freezer) Not actually going to use the refrigeration, but just us it for its good insulating properties.
500L Sump Tank (Chest freezer/ eskies sunk into ground )
Air (Lots, hooked up to my solar system, this will also support the back up)
Pump 1000-1500lph on timed intervals enabling to control when to flood GB's
Back pump from inverter which is hooked up to the solar system, only circulating water in FT.
Estimating that the size of the trout in system over the summer months will be around 500grams capable of raising between 30-40 trout (or around 20KG). possibly more if i only feed once every second day or so.

Of course I'm trying to keep the price down but estimate to following.
1000L FT $700
650L GB $50 (Already have)
Sump tank $200
Air pump $60 (already have back up batteries & solar back up)
Pump $70
Back up pump $ 40 (already have)
Miscellaneous items, plumbing, fittings, bracing ect... $200
Total = $ 1320.00
Estimated running cost for 3 months at 5.5Kw per day = $80


I'm planning of just collecting the main items so far and hope to have it up and running for this summer. So far I have managed to score the GB side of things. A broken down chest freezer. here's the pic's



Regards
Matt

Hi Mattyr,
I wouldn't say I'm frustrated but it definitely needs consideration and acting accordingly. I'm in the same boat as you - silvers slow etc. I had about 5 get the fungus and die. Not more since salting more heavily 3(ppt). I'm happy to be patient. If I can do Silvers over a few seasons and have trout every winter that's good for me. I like your fridge idea. I presume that you are planning on keeping the system going year round but only refrigerate in summer when necessary? My only though is - can you make the working fridge cold panel into the side of the tank rather than the bottom. If the refrigeration fails, there will be a major PITA to remove everything to fix. You may be able to make a removable panel that you can service etc.

Watching with interest.

Have you looked into fan forced bakki shower to keep the temp down.

could you run the water from your existing system through a chest freezer of water (ie sump) set at your required water temp via temp control on chest freezer.?

could you run the water from your existing system through a chest freezer of water (ie sump) set at your required water temp via temp control on chest freezer.?

Yep!!


That the reason why I plan on using a chest freezer, no need to build that system...
Also as a back-up I plan to repair the GB freezer in case the main tank chest freezer fails. also on hand is my 2Kw generator in case the power fails for an extended time.


No, Not fan forced??? is there a thread that you are talking about
Regards
Matt

Yes, i'm very frustrated........ like the idea of doing trout year round



You lost 5 this season, maybe 5 the next, maybe the lot like I just did. Its just too dangerous to run SP in Vic IMO, others will agrue this, like Food&Fish who seems to run his system faultlessly, but not everyones system is near perfectly setup like his.

I was happy to be patient and run SP since it was heavily stated on this forum that SP are a very tolerant species although slow to grow. I now have 3 tiny SP left from 50 that I have had for 19 months (no harvest) and have given up on them as a year round species.

Temps last summer meant that I could have run trout year round if I had any left. There is no guarentee that we will get another summer like that this year or ever again. So you either need to find a way to heat for SP or cool for trout. I'm heading down the heating path but the system will be a long way from completion. In the mean time I think I will give Jades a try since they have an apparently quicker growth but are less tolerant of cooler temps. To do this they will need to be taken out of the main system for maybe two winters and held in a heated indoor tank.

I will be following this closely.

I hear you - 19 months is a long time to raise 3 tiny fish. I also found the stall of the SP's pretty disruptive to vegie growth as well of course but still have a lot to learn so enjoy the challenge of trying to find a balance. Compared to trout who just go for it, SPs are a lot more work. I think its worth the effort though to raise an Aust Native that tastes good (hopefully I get to taste some sooner or later). Having said that - this Chilli Tank idea could be a hit...if you have access to all those insulated tanks and GB's....may as well give it a go. It will be interesting to see how much heat a properly insulated GB loses.

Don't know why you only ended up with 3 Silver Perch out of 50... or why you think they're such hard work...

They're probably the hardiest and most resiliant native species available to us..

If you can keep your water above 18... Silvers will continue to feed well... between 15-18 they'll become half hearted... and below 12 they'll barely eat once or twice a week....

But hard.... nah....

I like the idea, and interested to see how it all works but i'm wondering, isn't it cheaper to keep the water warm than it is to keep it cool or is it nearly the same?

Also, have you considered catfish great tasting and can withstand most temperatures.

Hi Mattyry seeing you are into refidgeration get the changeover valve set up from a reverce cycle air conditioner and put it in your large freezer then you can cool it for summer and heat it for winter

Yes I have thought about this but havn't come up with a soultion yet! There is a few things that need considering, needs a different heat exchanger and also Defrost...?

But reason why I'm Favoring trout is because.

1. I love trout! (most important)
2. only need to cool 2 - 3 months Max with trout, where as to heat I'll need to heat anywhere between 5-7 months.= more $$$ in power consumption.
3. Trout can grow out to plate size (300g) in 3 - 4 months. Silvers 12months even with heating.
4. I my case, I think the only time I've lost trout is because I have not had a cover over the tank and it resulted in oxygen posoning (Jumpers).
5. since i have a trade background in refrigeration, repairing chest freezers is reasonablity cheap.
6. My wife likes trout as well....


regards
Matt

No 6) will always determine your outcome

Still waiting to see how my silvers go over this winter. I got 25 from livefish 10months ago and kept them in the inside aquariums for a couple of months before they went into the ap, and they would be about 150-200g now. Got another 20 about 4.5months ago and they would be 100mm or so
Got 20 catfish as well 4.5months ago and they would be 100-150mm
Time will tell with these two breeds but if they dont work out then it will be trout in winter and jades (overwintered in an aquarium) in summer