Water change %

[bogart]

What's the recommended % weekly water change for an established tank? From what I've read it looks like 50% is recommended for new tanks. How long after a tank has cycled is it considered established?

 

[Luananeko]

50% is pretty common even after the tank is established, especially if you have live plants that you're adding fertilizers for. When doing fish-in cycling you change 50% any time the parameters need stabilizing, regardless of if its been a week. Many believe that small water changes (less than 25%) really don't change the parameter levels enough to be useful.

 

[gilpi]

What's the recommended % weekly water change for an established tank? From what I've read it looks like 50% is recommended for new tanks. How long after a tank has cycled is it considered established?

A lot of it has to do with the load you currently have, feedings etc. more fish equals more water changes. I'm not sure there is one set of rules on how much to change water but I do know the more the better especially if you have easy access to it, like a hose from the tank to the sink.

 

[bogart]

Water Changes

Thanks, it sounds like the safe bet is to always do 50%.

 

[fishyfriends3]

I do 25% weekly but then I do stock lightly according to aquadvisor I'm at 66% stocked.

Sent from my GT-I9195 using Aquarium Advice mobile app

 

[Proteus55]

I've found that 30-35% is about right for most larger (55 or so) established tanks. Every tank is different, but that's what I've done with great success for over 45 years or so. YMMV.

 

[Terrance]

50% pwc every single week for my freshwater tanks.

 

[jdempsey1980]

I have a 75g tank that has an overkill filter system to say the least. The filter is capable of running tanks up to 180g. With that being said, I do 25-30% WC every Saturday. My water continues to be stable & crystal clear. So I agree with everyone who says it depends on the the individual needs of your setup.
Tank inventory:
1- 8" Eastern Spiny Softshell
1- 7.5" male J. Dempsey
1- 5" female J. Dempsey
2- 2" Convicts
1- 5" Plecostemus

Everyone gets along just fine... As of the last 4 months since I added the softshell.

 

[Fresh2o]

I agree with YMMV. Good idea to test the nitrates and use that to determine the WC amount.

 

[threnjen]

I do 50% weekly, but I also have been dosing ferts in a way where this is recommended. I did 50% before that too, but a lot is because if I am bothering to do it at all I may as well do it 50% (I use a python so it is the same work either way, just means waiting a few minutes longer on both drain and refill)