Backyard Aquaponics
A place to discuss aquaponics

I still have my finger no pain, it just felt a bit rough before it decided I wasn't on the menu for lunch, there are no shark-like incisors

This is great info for me as I'm thinking about setting up a system!
Thank you for all the info everyone!

When I checked the system this arvo, with water temp getting up to 18C, I noticed the trout were rather lethagic, some swimming near the surface and able to be handled a bit- not a good sign! A couple of the deformed ones, including the one that swam around upside down a while back were dead, along with a normal looking one, all on the bottom. I gutted and we had the 2 larger ones 278 and 331g for dinner. The upside down swimmer is destined for chook food.
I figured that lack of O2 was the problem, as the output of the air pump has been decreasing over the past few months, although there was still a fair flow of air. I squirted water from the hose in for a while to get a bit more O2 into the water, and they seemed to revive. I've managed to find enough poly fittings to hook up the 12V Hailea to a battery and an air disk, which is now near the middle and churning the surface with air bubbles. Hopefully this will allow the fish to hang on as the water warms up over the next week of 30C + weather.
I've turned off the water to the one outside GB, in order to reduce the daily heat gain a bit, but the nights have been warm and the water temp is ratcheting up each day ;( I'll post a graph sometime soon.
I've got the freezers working full time freezing blocks of ice, hopefully it will be enough until some heavy duty chilling power arrives next week, and I'll transfer some fish to the big system and probably harvest a few from this one if the water gets too warm.

Hiya Gordon, I couldn't handle the stress of that many fish, good luck with them.
I had a look at the brand chiller you were looking at and couldn't find a kW rating (cooling). Do you plan on a primary or secondary refrig process and at what temp do you plan to maintain?
Do you still have the wave maker running?

Hey Skeg, yes, it's a bit stressful when I think of all those trout and look at the weather forecast!

Published specs are a bit hard to come by, but Aquasonic claim 5810W of cooling capacity. No matter how many times I asked, they could not tell me what conditions that was under - in and out temps, ambient etc.
The claimed efficiency seems far better than other brands like Teco.
I'll be putting it on the other larger system, and transferring some trout from this system to there if need be, and harvesting the larger ones. The Waveline pump is still running, and I'll just include the chiller in the loop for primary refrigeration, no extra heat exchanger, so the Waveline 6000 will be providing tank circulation, UV-C sterilisation, and chilling.

Teco.... Not heard of their water chillers, elect motors ok but their a/c's ain't fancy but they're cheap...
Bit hard to esimate cooling capacity without supply and return temps at a given flow for sure. Is there a built in pump?
Are they a tube in tube Evap? If so, apart from the uv-c, how are you planning to filter the water?

Getting to be rather OT for this thread, as the chiller is going on the large system...
No built-in pump, which is why I'll run it in series with the UV-C steriliser, driven by the Waveline 6000.
I have no idea about the chiller's internals yet, other than that the heat exchanger is Titanium, so will be fine for use in slighly acidic salty water and not poison the fish. As for the size of the tubes, plates or whatever they have, I don't know yet, but I dont have any filter on the Waveline input at this stage, so some fine particles go through. The pump water inlet is not far below the surface, so it doesn't pick up much in the way of larger particles.

Water and air temps for Sept. Yellow for this system, blue line for comparison with larger system.
The curves have started heading upwards over the past fw days, will post a graph of that soon.

I found one floater this morning, and another on the bottom, both decent plate size, but I wont be eating them!



The eyes were stuffed in a big way, both have been blind for an unknown period of time, but must have been eating recently, as they were not hollow in the stomach region. The eyes in one were falling out.

A search online suggests "pop eye" which has various causes. NH3 and NO2 are near zero, pH is low - mid 6s, water is crystal clear, Salinitiy 2.something ppt last I checked, and it will be about the same now.
Any suggestions as to what sort of ailment this might be? These are the trout from Tumut, and I suspect the water getting up around 22C may be rather stressful for them, so I might have to harvest soon. If this is some sort of infectious disease, I don't want to introduce it to the big system.

GG, I had this happen to some of mine a few years ago when I tried pushing them into the warmer months, but I had continual mid 20's water temps. Obviously not similar to your situation but could be stress related all the same.

Did you end up eating them Charlie?
No more deaths in the past few days, but the weather has been a bit cooler. I might use some of the ~100kg of ice I have stored next time the water is heading for 22C- perhaps these Tumut trout can't handle that sort of water temp. I know Russell at Arc-en-Ciel (where the trout in my large system come from) suggests that trout start to die at 22C.

When I went to check the FT this morning, I noticed a disgusting smell, and spotted 2 dead ones floating at the SLO+overflow drain pipe fittings , one of which had obviously rotted a bit and was hollow at the bottom front, although it didnt actually stink that I could detect (but I am just getting over the flu). The other one (493g) looked ok, but I decided to throw it due to it floating around in the stinky stuff- it looked mainly like oil droplets. I skimmed some of that off with a 4l ice cream container and took the lid off the FT, so I could have a good look around the whole tank, and let the nasty fumes escape. Fortunately no other dead ones, although I had been expecting them to all be dead with the stink!
I left the cover off in the light rain all morning, and put it back on a short while ago. The smell seems to have dissipated now, and they are all swimming around normally, although no one was interested in the half a dozen pellets I threw in, so I wont feed them today.

I tested the water:
NH3 0.25ppm
NO2 0ppm
pH6.29

I'm going to investigate having a Zn test done, as some water from the gal tank at the shed has been added to this system, perhaps enough to be a problem.

I might see if I can get my wife to give me a hand to harvest some in the next week days before it warms up again- big ones into the freezer, small ones into the big system tank, where I can keep things a bit cooler.

The lone Murray Cod seemed to be swimming around like a maniac when I was looking in with the whole top open, I guess it prefers being in the dark corners, out of sight.

With temperatures up to 35C forecast later next, it's tiime to start harvesting the trout (and moving any really small ones to the large system), so yesterday afternoon we netted out 16, pic shows 13 of them after vacuum sealing- we ate 2 and I gave one of the larger ones to a neighbour who gave use a hand.
Now there are only 2 of the 16 left in the fridge, as my wife knew some people looking for some "dolphin friendly cat food"



Largest in this lot was 609g. There were a few deaths one day early in the week, and one of them was 670g, with nothing apparently wrong with it.

I'll probably take another 20 or so out tomorrow.

Sorry

Is it the large volume of grow beds which causes the FT temps to follow the air temperature? Just wondering how mine are remaining stable. Or perhaps if I was logging the temps instead of just looking now and then at the thermometer I would see something similar. I usually look in the morning when I feed, and in the evening. Wondering because I have such small grow beds, maybe it is less of a heat sink?