Backyard Aquaponics
A place to discuss aquaponics

Eeek, help!!!

Thought we had everything nicely prepared...

1800L round gal tank filled with -
1700L rainwater (from food-grade plastic rainwater tanks, just the day before adding fish). Rainwater tanks have had first flush diverters fitted, so water in tanks fairly clean...
2 stainless steel grow beds (bought 2nd hand!) approx 1800 Long, 45cm wide, 45cm deep
filled with scoria - washed to remove 95% or more of dust...
Got some filter muck (around 500ml?) from a friend's healthy aquarium, and 20L water from same aquarium, poured over scoria...
Bought large air pump, does 4200L/hr (not sure if this is air or water - not stated on box and have no experience with these previously) capable of running 10 airstones.
Fitted 4 x airstones, 10cm x 10cm.

Picked up 20 rainbow trout on other side of Melbourne this am - they were bagged around 10.30am (with O2 pumped in, from Macclesfield trout farm, very nice and helpful people)
Were a lot larger than I'd expected - around 6" long (maybe longer?) and 2" high?
Released into our pond around 1.00pm - they told us they would be fine for 3 hrs, but were gasping in the bag when we took the bag out of the esky with blanket over.
We didn't let the bag acclimatise to the pond temp as they looked stressed, just opened the bag and got them into the pond and turned the bubblers on.
They leapt around near the top of the pond getting O2 as the fish farm guys said they might.
Very quickly they settled and were swimming happily around the bottom.

We decided to keep the air going, even though the fish farm said they wouldn't need it in Winter, as we thought we would compensate for their lack of O2 earlier.
We have been flooding and draining our 2 scoria beds every 2 hours.

About 4 hrs later, some friends visited, and distractedly, I suggested they try giving them some Azolla weed I had been given Friday am. (I'd had it in a plastic bag since then.) I'd been told that fish liked to eat this stuff. About 2 tablespoons full or so were put in.
We had just tested the ammonia levels at around 0.25 mg/L or ppm.
About 1/2 hr later the first fish died. Then another 4-5 quickly afterwards.
We removed as much as we could of the Azolla.
One of the friends used to keep fish and said that when they brought tropical fish home some would always die, so we thought, OK, it's normal.
Ammonia levels were about 0.5 ppm.
We removed the fish as they died, and in an hour or so the ammonia levels were back down to nearly zero.
Trouble is the fish keep dying.
Now its 9pm and I think we have around 7 left? 3-4 look really healthy...
What can anyone suggest? Was it the weed? Was it because it was in a bag for 3 days?
We gave them a little bit of food an hour or so ago (10 pellets from the trout farm as there were 10 fish left) (there was a lengthy discussion about feeding or not to feed under the circumstances...)and they haven't touched it.
An hour or so ago I planted some seedling vegies..
Any suggestions??!! The flower really looks a bit too happy for this situation...

Whats the temp of the water.
And have you added salt to the water.

No salt added.
Temp was approx 16-17C in water today in Melb, air temp around 25C.

have a look at this thread....It is a very wisely written thread ....About handling a dud bag of fish.....

viewtopic.php?f=29&t=1740

ph at the trout farm? ph in your tank?
Gal tanks are a worry with zinc leaching, is it gal or aquaplate?

Didn't measure pH at either end...
Should next time I take it?
How do I safely adjust pH at my end if too high or too low - do I just use stuff from aquarium shops?
Tank is galvanised steel, soldered.
The tank left to weather for at least 6 months before filling.
Tanks cleaned with water before filling with clean rainwater.
Did feed fish a little bit of Azolla that I had in a bag for 3 days - this was perhaps not a good idea?

possibly didn't help, but may have been ph shock. If yours is too high, use small amounts of acid, eg ph down from a hydro shop to bring it down a bit. Because you didn't acclimatise the fish, they may have suffered from different water parameters.

Big ph change can kill fish. Low ph in a gal tank will release heavy metals into the water. But not sure how long it takes.
Beaten to the post.

transfer fish slowly, adjusting temp and water quality slowly.
Adding water to the bag slowing will oxygenate the water a bit. this should help.
gasping in the bag suggests too many fish per bag or the bag got too hot.
The fish were stressed in the bag, then you perhaps severely altered their water conditions.
After that you added azola, was there water in this bag? It's possible this water had a chance to go fetid, but I doubt this is the cause so much as the lack of oxygen stress and the shock of condition change.
Really sorry to hear about your losses, I will ask them to bag more liberally when I go down.

Actually I just had a l9ook at the post Jessy linked to. Read that. It is VERY thorough.

Thanks, have just read it through too - was very thorough.
As we were not experienced with what stressed fish looked like, panicked when their little mouths were open and gasping..thought it was better to just get them out of the bag.
So then it would have been better to get the bag openbut not actually added in straight away...
The fish farm said that trout were good acclimatisers to diff temps, but being new to fish tending...seems like it would have been better to be more gentle with the transition.
And yes it seems that more adequate bagging may have helped.
It was warm in the car today...
Hope your mission is more successful!!
I think we will try goldfish for a bit!!!

did the fish bag travel in a foam box or esky?

The heat in the car would have been the initial problem.
Excess ventilation is always employed by myself when moving fish. A car is like an oven, fish last less long than dogs, or even babies for that matter.

patience and time...we all kill fish for what ever reason.

Just keep searching this forum.....all the answers are already here....just a matter of finding them..

and not all answers are your answer....a matter of research and deciding it on your situation...really matters in the end

Good Luck and go Forth

Thanks Jessy, and every one else too...