Need advice : Fish keep dying in quarantine tank

[zulkmc]

Hi there,

I have a 3-month old bare-bottom quarantine tank, with PVC elbow-pipe for fish' hiding place.

Everytime I purchase a new fish (e.g. 2.5" Flame Angel or 3" Blue Tang) and put it inside this quarantine tank, it's breathing will be rapid & it will sadly pass away the next day.

SPECS :

Tank size : 40 litres

Filtration : Sponge filter, air-pump driven

Water change : 30% everyday; salt mix with tap water & chlorine remover, aged over 24 hours

Temp : 30 C

pH : 7.9 - 8.0

Ammonia : 0 ppm

Nitrite : 0 ppm

Nitrate : 15 ppm

Copper : 0.15 ppm

Any advice or comments are welcomed.

Thank you.

[chrislwp]

I have the same size 40L quarantine tank as u, however I am running a Ehiem canister filter. A sponge filter like yours may not be good enough, so I suspect the following reasons:

- ammonia spike somewhere, though u maybe measuring 0ppm at certain timing

- Ph shock maybe when u change 30% water

- copper poison

- temperature

- already a sick fish, and u further stress it with the small tank and copper dosage, and instability water parameter

I suggest u install a canister filter to stabilize your water, should you need to change water, use your main tank water. That's what I did when I quarantine a 5" powder blue for few weeks. Do not overdose copper, if you are using cupramine, I am dozing 15 drops and observe fish behavior..

[digibee]

Hi,

I think you should fill up at least 50% of your QT water from your DT (matured water).

The rest of the water can use saltmix.

And use a fan over your QT.

You can actually just change 10-20% of your QT water with saltmix daily.

Cheers!

[zulkmc]

I think it's the inadequate sponge filter too.

Will heed your valuable advice.

Thank you.

[zulkmc]

To both Chris & Digibee, thank you.

[digibee]

Also note that; evaporation will be high when you use fan;

So, you can actually top up with fresh water if you do not change water daily.

That is what I am doing; and I have no problem with my fish in QT.

Usually I change water in my QT once in two or three days; but top up with fresh water daily.

Cheers!