When to do a water change?

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Catkramer

Aquarium Advice Apprentice
Joined
Dec 31, 2008
Messages
13
Location
Utah
I don't want to do a water change if the amonia levels are up, right? I need those to peak so that the bacteria will grow? I only want to do a water change when the nitrites go up? Maybe I am confusing myself.

My amonia right now is .25 mg/l on the little card. And my nitrites are safe. So I wait? I was told to wait another week to do another water change, but I want to make sure that was correct information.

Cat
 
yes, u need them to peak and then drop back to zero. Ammonia is bad for the fish.

When I was cycling my tank I only topped off the water level as needed due to evaporation.
Hang tight and some of the others will chime in with more friendly advice.
 
Thank you! I just want to make sure that I don't sit too long and make my fish sick. I have some babies in there and I would hate to do something that would cause them to get sick or die.
 
As I understand it, unless you are cycling fishless, any time ammonia or nitrItes are over .50ppm go for a large water change. 50% - 70% NitrAtes need to be kept below 25 - 50 ppm. Lower is better. Keep testing the water daily if possible for ammonia and nitrites.
 
If you have fish in the tank while it is cycling, you need to do as many pwcs as it takes to keep the ammonia and/or nitrITE level down below 0.5ppm. If you can get it closer to 0.25pm that's even better. Any higher than 0.5 and you're risking the health of the fish.

If you were doing a fishless cycle, you can keep the ammonia levels higher than that because there is no livestock. The bacteria will still grow, but it will take a little longer. On average, cycling with fish can take anywhere from 4-6 weeks, give or take.

You can shorten the timeframe by getting some filter media from an established tank and putting it in your filter. Know anyone with a tank?

As Jim suggested, it's probablya good idea to test daily and do a PWC if those levels go over their benchmarks.

Good luck.
 
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