Backyard Aquaponics
A place to discuss aquaponics

Had first SP fatality this morning ,found it still on the bottom of FT but already cold.
One of the smaller ones, 80 mm total length.

No apparent reason, looks healthy but lately I could hear them bumping into the FT walls in panic
when approaching during the day.

Also, after adjusting to maximum the off period between each pump I turned on one airstone and it was keeping some of the uneaten disintegrated pellets in suspension.

Did do full water quality test:
PH-7.3, Sal down to 0.35mS, Ammonia – about 0.7, Nitri and Nitra on 0

Finished work on a minimum/maximum thermometer with reset.
Doesn’t go below 0, wouldn’t need it here, hopefully, and only whole oC, no decimals yet.
Works great on a protoboard, but will see first if I can get one cheaper off the shelf
that would do the job.

Problem with them is a long cable from the temp.sensor to the electronics and display
could give inaccurate readings.
With mine I can keep the sensor and electronics close together with a long cable to the display.

Hi Steve.. It seems u have a little bit of ammo, which would be bc of the uneaten food. That uneaten food combined with upping ur off pump times have tipped one of the weaker small ones over the edge imo. (Notice the black spot near the anal fin in the photo, an indicator of suboptimal O2 conditions.)
Perhaps just run the pump for one cycle during the night. Only feed them what they will eat. I am only feeding my 200 littlies a small (Very small) scoop 2-3 times/week. I have a tshirt over the return line to get those extra fines out that the gbs miss.
My water varies b/n 10 and 13Catm. If I cut my pumping cycles after dark, it would be a bit higher I am sure, but the stability is the thing now, as I am away a lot.
I haven't had any fatalities and my water is pretty clear.

Thanks TT, the ammo reading really surprised me,
and I did try to do the tests by the letter, but with nitri and nitra at 00 ?

Are the bacteria hibernating? two trays of duckweed in the FTs doing much better than that in the B container.
For some time now.

Turned the pumps off period to max when advised on the onset of the cold weather, but also turned on the airpump permanently, had it on Back/Up before.

Were vacuuming the uneaten food but there was always some leftover, kept in suspension by the air.

Not a physical lack of O2, but a combination of what? Cold water and ammo and ???, Just guessing.
Also, when approaching, the SP were getting into a panic mode, running for a cover and bumping into the FT sides.

Did do 1/3 water change, put the air back onto B/Up and turn on a small pump cycling water
from the upright tank into the FTs to oxygenate without stirring the water from the bottom.

Do have a filter on the return pipe from the GB to the sump.
So far so good, no food for three days now, but saw them feeding an algae
and much calmer.

Will do another test tomorrow, were really busy last two days, contractors tearing the driveway and front yard, tomorrow they will start concreting, will no try to help with something I know little of.

Will try to hook up some rudimentary Solar heating sys to see if it helps.
Do appreciate your input

Hmm, I guess its just a wait and see what the readings do then. That is a surprising ammonia reading for a cycled system when no fish have been added...

OBO, went to see them just now, can see them clearly at nite with a torch.
Have three SP rolling, swimming uprite/ upsidedown.
Water quite clear, no food in suspension, ???

Will se what the test shows tomorrow.

Steve, google 'swim bladder disorder'. That is what is causing the 3 to swim upside down. Pls don't feed. A full tummy puts pressure on their swim bladder and they lose equilibrium, ie, upside down. I had one last year, also had half his tail eaten. Tuff lil fella survived which is not normal. Lost a few at the time. It was poor water quality and inadequate pump cycles that did it, chuck in the cool wqater temps and I think I lost half a dozen 20cm fish over the course of a week.
Duckweed would be stripping O2 from the water at night which compounds the not pumping thing at night.

Steve, missed the top posting for some reason - are you using the DS18B20 temp sensor

Have started pricing and purchasing a few parts to get a temp sensor project out of the planning stage...looking at another project to read water levels and add water to keep sump at a controlled level

Thanks TT, found a lot on it,
One of the Urls, “http://www.fish-disease.net/fish-disease.htm”

Last nite , after posting, put in 2kg of pool salt,
One didn’t survive (84mm), but the other two do not look worse,

Test from this morning – salt- 2.55mS, PH 7.1, Ammo 0.5, Nitri 0, Nitra 0

Did nearly ½ water change and added 1 kg of salt to bring back to the original level.
And hopped it didn’t make thinks worse. Didn’t feed them.

TT, I wouldn’t expect O2 problem, replaced the air pump with a small pump
that cycles the water from the upright tank into the FTs fulltime,

Goldies and SP are in the first and second FT while the duckweed in the last two,
with one on line but unoccupied in between.

Don’t want to stress the SP to much, but would it help if I split them into two tanks.
For the spring getting ready one IBC for them. Already installed and some pluming done.


EllKayBee, yes, it’s a DS18B20 with 8M picaxe and a Serial LCD module.
Will try a strait LCD with a 14M to make it cheaper but not sure if I’m up to it.

Thanks for that Steve, I have been reading up on the temp sensor and seem to have them all worked out

Have Saturday planned, but will have a look at what you are trying to do and see if I can work something out

Dunno about splitting them atm Steve. I wouldn't be doing too much with them til the water is consistently up to 15C. Moving them at temps now would cause them to stress further. I know John at Glenwaters won't touch his around 10C, just too risky. Your fish are from him via me. I think u get a bit more temp variation bc of a slightly lower volume of water in ur system. I have about 6000lts over 2 tanks and 12C is about it atm. Biguns and littlies feed twice/week.
Hang tight, don't feed and keep the air up. Things should start to warm a little in a month or so.

wilco TT, thanks

Got delivered 4 (cubic)m of 14mm red scoria.
Any easy way to wash it?
My preferred would be to spread it thin and wait for the rain to do the job.

And there’s one I prepared earlier.

On the previous delivery have ordered enough extra scoria to finish the nine new ½ b/barrel GBs connected to an IBC.

With two pumps in the FT, one for each row of GBs and a smaller pump permanently on
recirculating the water to oxygenate it.

Had it running(in) for 5 weeks now with two small goldies in it to test the water.
Running just one pump on a timer at a time and alternating them weekly to flush the GBs.

Did wash the scoria pretty well, the water is only slightly tainted.

Last weekend my goldies in the barrel were already scrambling for the pellets
but SPs didn’t show any interest, just run for cover.
During this week were working 6 to 6 so did see them only at night.
This morning fed them a bit but they scramble for cover when I approach and stay hidden behind the pump.
So don’t know if they ate anything after I left.

Will wait another week or two before moving some of them to the IBC to see how they will fare and to start this setup, then the rest will follow in as well.

Still working on the timing sys. for this setup.
Works well on the mechanical timers but its got no HSM mode detection or emergency backup.

Also got my two channel digital thermometer working I wanted, if the batteries are not flat but I still have to waterproof one sensor and make an extension cable for it.

Have been back to work for the last three weeks already and little spare time for all this.

Daytime pic of the goldies and SPs at nigh, with a torch light.