Backyard Aquaponics
A place to discuss aquaponics

Today (so far) three of my barra have died, found on the bottom of the 1000lt tank with gills flared,they have been in for close to four weeks, with no problems, they ate all the feeder fish and started eating 6mm pellets, then the temp dropped a few degree's and they stopped eating,There was some young kids here last night, and I found the net in the tank this morning so I thought it may be stress when I found the first one, but a couple hours later there wer two more dead, They are sitting in the air bubbles and moving around seemingly happy, they do have a furry like look about them. I have 20(17) in a 1000lt tank, approx 250mm, for 4 weeks temp has been cool, down to 17 or so, its been this all the time,sometimes up to 20 during the day nothing has changed except they have stopped feeding, and maybe stress from the kids. Any ideas ?? Stressing me out now...

Probably too cold for them IMO, and if they are furry they will have fungus. Salt the tank, and warm as much as possible to get them warm

As FB says... A bit cold still and I'm guessing perhaps a fairly new system?? If the system is fairly new, stop feeding.. If you have a test kit, test the water and post results.

checked this morning, another 6 had died, salted tank, 3kg/1000lt, wait and see, and will warm the water up as well. So far have lost 1/2 my Barra (10), a bit dissapointing but a learning curve for me I suppose. Will the salt be ok in the tank when they get better, and if they get that fungus could I put more salt in, question being water evaporates but salt wont, what would be the max total salt in and would I have to change the water when I want to put trout in next winter?
Thanks for your help

The plants will take up the salt. What sort of salt did you put in?

Barra dont like the water below 22 for any length of time. Under 22, there immune system gets really low and they will pick up any germs livig in the water. I also learnt this this hard way, loosing 30 400gm barra.

Apart from temperature, what are the water quality results? Ammonia, nitrite and nitrate?

Sorry but if you want to grow any of your fishes bigger before they die, you need to educate young kids that you have coming around your houses that these are living creatures. Putting a net it and swirling the water around would definitely stress the fishes out, especially when they are already coping with the stress of low water temperature. For goodness sake, if you are going to get barra before the water temperatures are constantly above 20degC, put a big enough heater into the tank to heat the water. In case you don't already know, temperature flunctuations also stresses the fishes out... so yes water might heat up in the day but it will cool at night. Try measuring your water temperature at 5am and see what they are... that would probably be the coldest...

Could the kids have added something into the tank that was not meant for fishes??

Sorry but I have seen many young kids these days that have no respect whatsoever for fishes and probably small animals as well.

17 is too cold for them my friend... I also agree with Ivan that you don't want your young tackers stressing the fish out. My tanks are strictly a no go for the kids.

Out of interest I had my water temp drop to 12 one night in winter and did not loose any Barra. They were just a little dopey. My over night temp is steady around 26 deg C at present.

It was pure salt (no additives)the rest of the fish are looking better, took the shadecloth off to try and bring the temp up while chasing a heater. Haven't got a water test kit but will post results when I get it done. Definatly no more kids around. Cheers for the help...

Barramunchie..... I think your biggest problem is you started looking for answers when there was a problem, if you had done the research on BYAP or elsewhere, you would have known the answer to every question you asked on your first post.

no test kit ....tch tch tch

I never use test kits.....

But you have the experience to know how your system is performing with out one. I was shocked when I got my test kit 3 months after starting my system. I thought everything was fine. I stopped feeding when the fish (currently Trout) didnt hit the food hard etc, but discovered that what I thought was fine actually meant an ammonia reading of 2 and nitrite of 4.

Yep... everything will look fine... without a test kit....

And dead fish look perfectly natural... just dead... and you don't need a test kit to figure out they're dead...

To avoid the above... get a test kit....

And ask questions about the temperature tolerances of different fish species... if you're unsure....

We're all here to help...

and when it starts to smell!...... Then theres definitely some thing wrong,

Been there!

Or at least bring your water to be tested by one of the local aquarium shops... I think Vebas is near you... Ask them to test for ammonia, nitrite, nitrate and pH... the rest of the tests that they can do are not relevant to AP...

Also if you are looking for a heater, I think Vebas do sell heaters as well.. Try the Ehiem Jager ones... they are a bit expensive but after 2-3 years, they will still control the temperature to what you set it at... the cheapers ones will most likely lose their thermostat control after a year of operation... But make sure you protect the glass of the Ehiem Jager as barramundi are big fishes and can break the glass when they panic swim... What I have done was to take a 40mm PVC pipe, drill numerous holes into it and it acts as smash protection for the heater...