Water Change

[Toysoldier]

Dear Docs,

i just did an 80% water change becasue i cannot stand the sight of the yellow colour water anymore caused by adding quite an amount of black water after the jumped last week...

initially i only did a 30% change...but the colouration is still there...

so anyway i did my 80% water change and add generous amount of salt... (now it is in the 2 'tank)

and off course anti- chlorine....

would that be ok? what are the disadvantages or "not advisable" to do it ?

[kenneth]

Too much water change lah. Limit yourself to 30% max unless it's a medical emergency. Even then, use aged water only. Anti-chlorine not so good, age the water 1 day by aerating it is so much better. That's why we don't change so much water all at once.

Generous amount of salt ??? You gotta be more exact hor! Calculate the amount of water in your tank, weigh your salt. Add 0.1% for normal use. For medical emergencies increase 0.1% over a few days until reach 0.5%. No more than that otherwise you end up with salted fish.

[Alvin Koh]

Kenneth,

There are alot of issues with huge water changes like that.
There is the difference in temperature, the sudden stresses attributed to a sudden change in water parameters like pH.

It is one of the last things to do because it is easy for an already weakened arowana to deteriorate in terms of health.

Such a large water change is not recommended. If you really want to do a large water change, I recommend you stagger the replacement of water.

Drain 50% of water. Replace 10% of water every second day until it's filled to the desired level (fishes take days/weeks to properly adjust to new water parameters, not hours). The stressed associated with such method is significantly less.

Alvin.