Backyard Aquaponics
A place to discuss aquaponics

Hello all, I seem to remember reading about fish being at the top of the water, and drinking air. I can't remember where I read it, and have looked in the mags and not found it. Can anyone enlighten me as to where I read it, and what does it mean?

I have 2 air hoses in the water and the water tests are fine. Only a couple of the barramundi are doing this.

They (18 of them) are feeding well, temp is 26 today, 1000 lt tank

Any suggestions? Is it anything to worry about?

Linda

Well I also cannot remember where I read this, but two main reasons for a fish "drinking" air at the top...

1) Not enough air. As water gets warm, there is less dissolved oxygen in the water, so fishes may struggle to breathe in the water hence coming to the surface. Although you did say you have air hose in the water, just check that the stones are not blocked... give them a wash (scrub, rub)... and check that your air pump is still functioning as before in terms of air volume... I suppose what I am saying is if your barra has survived for full heat of summer a few weeks back with the air you have, the only thing is that the air volume has reduced due the above issues...

2) Nitrite poisoning. The fishes may appear like they are looking for air but really it is nitrite poisoning stopping the blood from carrying oxygen to the body...

If the above have been ruled out, then it might be something else... Over the past week, due to drop in temperature, barra should start eating less, so make sure that there is any uneaten food left at the bottom of the tank... any uneaten food would turn the water bad and hence the fishes would start to stress... You should check your water temperature first thing in the morning, preferably before the sun heats up the tank... cold overnight temperature could drop the temperature of the water lower than what you measure when the sun has heated up the tank...

Thanks that is helpful. I'll go check the air hoses and supply.

And salt to 1ppt as a precaution....

Forgive my ignorance, how many grams of salt for 1000 lt tank?

1ppt is 1kg of salt per 1000L... and make sure it is sea salt or natural lake salt...

Tks, I have some crystal pool salt that I use for other things, so I assume that is OK?

Probably... pure seasalt is best... most pool salts are...

Buy a bag of "Sunray Pool Salt"... Bunnings/IGA.... 20kg from $7-$10....