Do we need to change water even when the tank is stablised ?

[k3nni]

Hi guys this question may sounds abit stupid ,cos i heard alot of pple said that once water is stabalised normally u dun change water already .But how often do u pple change water after it stablised or just add water will do ? if u guys still change water how often do u all change and how much ?

[michael lai]

Hi k3nni,
Don't worry about the questions, don't know ask. In regards to your enquiry, yes you still need to change water even when the tank is stabilised. How much would depend on what setup you have. Planted or fauna. What sort of fishes, big, small, many or one. Goldfish will foul up your water real fast. So will big fishes like catfish. The tricky part is knowing how much to change. You wouldn't want to bring the 'matured tank' back to square one so 100% is highly not recommended. I'm not too technically inclined in this area but as a thumb of rule.
A) Normal=25% change weekly or fortnitely.
B) Bad =50% as and when required.
Good bacterial also die when it comes in contact with chlorine in new water.
The reason for the change besides water getting dirty is also due to accumulation of undesirables such as ammonia, nitrite and nitrate which also affects other water parameters that can harm or irritate your fishes. I'll leave the REAL technical stuff to the 'GURUS' but I hope this helps.

[blueray]

Agreed with bro michael lai even when the tank is stabilised we still need to change water. Just that the frequency and amount will be lesser

For my 3ft, I only change about 20% monthly instead weekly.

[|squee|]

It's more of a individual tank judgement for me. For my 2ft, I use the Estimative Index so I have to change 50% weekly no matter what.

For a low-maintaince planted, no change is reccommended. For fish-only, I change bi-weekly 50%.

Truthfully though, once the tank, or filter in this case, has matured/stabilised it's rather hard to do damage through water changes imho.