Backyard Aquaponics
A place to discuss aquaponics

This morning there were just 3 left and placed black corflute all over the tank and tested the QT.

So, armed with all these new ideas I figured I'd go and get another 30.
I got to speak to Mitch (the owner) about what I did and his thoughts on the changes to the intro strategy I was about to do.
He said the salt level wouldn't have been the problem because they are often sent to areas with brackish water.
Light in and around the tank is a problem and although they'll come out into the sunshine they prefer to spend most of the time in the darkest corners.
Aeration devices producing bubbles should be kept to a minimum so the popping bubbles at the surface create minimal disturbance. He also told us of a new aeration pump and pipe system they trialed that caused too much mechanical vibration in and on the tank they killed heaps of fish. So suggested any vibration will over stress the fish and that I should remove the aerator from the top of the tank.


The new batch arrived home with a fully inflated bag, I placed it in the QT opened it and clamped the side to the tank opening. I un-clipped the air hoses off the SLO and placed one in the bag and took some test water. It showed a Ph 6.4 against 7.8 for the QT and the ammonia was up to 0.5 ppm in the bag.
I figured if I took a liter out of the bag and replaced it with a liter of QT water every 45 min I'd be reducing the ammonia while increasing the ph. I've done two changes so far.
The water temp is 14 C.

Pete.

You should be OK doing this and it's much better than just dumping them in . You'll be increasing the pH in the bag as you replace water with QT water. At higher pH the ammonia becomes more toxic but even at pH of 7.8 with the temp you currently have the ammonia won't hit the toxicity level. It becomes toxic around 1.2 or 1.3 for the TAN reading at a pH of 7.8 with 14 C water. I might not do this correctly but I suspect 45 minutes is more than adequate and you could probably go quite a bit faster but I'm not certain of this. Changes of 0.3 to 0.4 pH units with some adjustment time between changes is probably good (it's not super critical and some fish can take a lot more than others (trout seem pretty sensitive but I think they'll be fine even if you're off a bit))

http://ibcofaquaponics.com/information/tables-and-charts/

Hope things go better this time around, I'll be rooting for you

what is your plan for aeration ? Putting a submersible pump in the tank would presumably have the same issue.
And trout need a pretty high DO. You said the farm had a flow aeration with water pouring in from a pipe (and presumably overflowing like a SLO) - can you emulate this ?.

6.4 to 7.8 is a pretty big pH jump. This may have been a factor before.

Also the black is good but it will/may make the IBC hot in full sun - you may need to wrap something light around the corfulte. Maybe put your white shadecloth around the whole lot. keep and eye on FT temps.

hope it goes better this time.

>> the ammonia was up to 0.5 ppm in the bag.

may be the ammonia was up a little bit in the original water and the fish have added to it.
oxygen filled bags are pretty normal way to transport, and you only had 30mins drive.

The idea of changing the water in the bag seemed logical to achieve two important things (but I didn't know the toxicity levels Scotty mentioned) but after the third change I did another test and found the ammonia 1.0 was building far quicker than the PH 6.6. Also the water seemed to become cloudier white whereas it was a dirty pale yellow earlier. I thought they're either going to die of ammonia overload or Ph difference. I didn't want that water in the QT so I scooped most fish out with a net and put in the QT, the rest were poured into the suspended net out near the GB's then placed in the QT.
All fish seem more relaxed and even took a feed at dusk.
I remover the air compressor from the tank roof and reduced the flow which lowered the vibrations by 95%.

I've got some white corflute I can put over the top for the next couple of days.

I am wondering now whether I should increase the salt level again - what do you think?

FT 1 is clearing up nicely as I can see everything in the tank although there is a brown stain all around the inside from the Powerfeed.

I might have got it right this time....

Pete.

The idea of changing the water in the bag seemed logical to achieve two important things (but I didn't know the toxicity levels Scotty mentioned) but after the third change I did another test and found the ammonia 1.0 was building far quicker than the PH 6.6. Also the water seemed to become cloudier white whereas it was a dirty pale yellow earlier. I thought they're either going to die of ammonia overload or Ph difference.

yep, hard choice to make but the ammonia is definitely not great for the fish.
The pH jump is not ideal either.
Next time (hopefully next year) better to try and get the QT much closer to the hatchery pH.
Maybe get something set up to collect and save some rainwater (but be careful to avoid zinc/galv etc)

All fish seem more relaxed and even took a feed at dusk.
that alone is more positive than last time. Best not to feed them too much.
Just bare minimum - they will be fine for a few days.


I remover the air compressor from the tank roof and reduced the flow which lowered the vibrations by 95%.
interesting point about that one. Hopefully that helps. Else maybe have to use a side pump in a drum and pipe feed water, gives option for a tub of media for a longer stay and some filtration and added aeration.
But many here would simply have an airstone feed....albeit without the vibration

Scotty has an interesting point along that line when he said (post on previous page):
"and trout are very sensitive to electrical currents as well but mostly I think they sound stressed and they need some quiet time without visits. Make sure the water has 1ppt of salt added for stress and dim down the light a bit if you can."


I've got some white corflute I can put over the top for the next couple of days.
white would help. Try and make it as shaded as possible. Hopefully you don't have too many hot days.
For this and your main system I would probbaly be looking at better thermal protection - say something padded and silver reflective like an insulated blanket (eg. like they use for car windscreen sun shades)

I am wondering now whether I should increase the salt level again - what do you think?
Maybe keep it at 1-2 ppt and see how they go for next 24 hours. You don't have any other fish in your system
so this time will be OK if they look healthy (what happened to the 3 remaining fish ?)

I might have got it right this time....
Might be worth looking at your main system fish tanks and getting some form of lean to or something over them. Keep and eye on both the QT versus system parameters - you want these to end up the same in a few days time.

You did the right thing Pete . I kind of wondered if you were going to have that problem which is why I gave you the levels. Definitely salt to 1ppt. You can go higher if you like (Unless they look sick or show signs of flashing, I don't think I would) - dissolve the salt in some tank water before adding. The fish will be producing ammonia - the more feed, the more ammonia so think about your filtration and you should be OK.

18 left...

I pulled 11 out this morning, then another 4 by 10.00.

I tested the waters of the QT & FT1.

Because I don't have filtration I think I'm going to be in the same boat as the bag. So I've started putting 9 liters per hour (4%) of FT1 water into the QT to try to bring the Ph's closer before the ammonia becomes toxic.
I caught some rain water and have been topping up FT1 with it.

These last 18 are giving me hope that I'm doing the right thing as none have died since beginning the dosing.

It's getting me down now.

Pete.

Aw man, that's a shame Pete.

sorry to hear Pete - there is definitely something amiss.

as soon as pH is equalised get them across in to the main system and see how they go there.
(just watch for temp differences when you transfer - don't need temp shock added on)

I'm curious, why are you testing both low and high pH? It's either going to be one or the other.

>> I'm curious, why are you testing both low and high pH? It's either going to be one or the other.

around 7.2-7.6 the API can move around a bit and disagree. Its not really that reliable compared to a digital meter.
(applicable to QT but not issue on the second FT one)

and he is bringing the QT up through 7's (so across low-high) to match the main FT level around 8 .

When it rains it pours

If you haven't stopped feeding them you should do this for the simple reason that feeding will cause more ammonia to be produced. Also make sure you maintain the salt levels in case nitrites start to become a problem. Probably should test for nitrites in the QT just in case - I don't really expect any at this stage and without filtration but play it safe.

Fair enough. I'd like to get a decent digital pH meter. The cheap Kekida one I bought is useless, so I've been relying on my interpretation of the API kit.

15 have survived the Ph raising.

This mornings tests looked promising so I added another 18 liters to the QT and replaced 18 lt with gassed off stored mains water. I added 100 gm of salt to replace the lost salt in the 100 lt that went into the QT.

I set about vacuuming the inside base of the tank, lining the outside FT1 with the black corflute I had left then resurrected the the SLO and air pump with air stones cable tied on. The air lines were not long enough to to mount the air pump off the off the tanks so I placed it on top of a towel on the next tank, FT2. In the mean time I was slowly draining the QT to increase my chances of netting the fish quickly.

I'll wait till this evening to see if they want some feed, at the moment they're in the bottom corners of the tank.

Pete.

Fingers crossed!