Backyard Aquaponics
A place to discuss aquaponics

Hi new to AP and we have just set up DIY IBC system. Tank is about 700 Lt istalled pump (2200L/hr) and have running 15mins on 15mins off.
introduced 50 silver perch on friday afternoon now have 7 left!!!
Water test are as follows
PH 7.6, High Range PH 8.2, Ammonia 0, Nitrite 0 and Nitrates 0.
Added a litre bottle of water from existing AP system.
Concerned about water quality comes from corro tank filled by the Hunter River and does have high levels of Iron is this a prob?

Fish all dying with open mouths and flared gills.
Thought we would kill some learning but not so many so soon obviously we have a major problem. Any help appreciated.

Hmmmm, hard to tell really... Do you have another water source you could use?

What sort of aeration do you have... a small 700l corrugated tank would warm quickly during the recent hot weather....

any idea what your water temperature has been lately...??

Your description of the fish suggests DO starvation...

The tank has a aerator that's spose to do 450lt tank plus the draining of the GB could this not be enough?
The tank is plastic and lined with insulation and has colourbond surrounds to help keep sunlight out.
Water temp 23.3

Water temp wasn't that high... and your aeration sounds OK....

but 50 fish in 700L... humm... how much does the tank drop when the system pumps???

And you say the tank is lined with insulation... I presume you mean on the outside??

When the System pumps and GB is full there would be approx 550-600lt left in the tank.

The tank is plastic and is lined on the outside with corrugated tin surrounds to help keep the sunlight out of the tank.

Maybe you want to get a second opinion of the water test... bring a sample of your water for someone else to test with their test kit or a local aquarium shop...