How much percentage of water should I change weekly?

[Retrixy]

I have a 105 litre tank/23 gallons and i'm going to have 1 Axolotl in it. How much water should I change weekly (7 days)?

 

[Binditheaxolotl]

20-30% every week

 

[Calgarycoppers]

I do 33-50% weekly in my no plant tanks

 

[Murk]

To chime in as well: if you have a nitrates test kit (which I assume you have?), you can also test the nitrates, wait a week and test again.
Once you know how much the nitrates rise every week you'll also know how much water you have to change every week.

After you do this for a few weeks, you'll know how much water to change specifically for your tank and your axolotl.

 

[Retrixy]

So how would I know how much water to change based on nitrates? Could you give an example?

 

[Murk]

So how would I know how much water to change based on nitrates? Could you give an example?

The other two answers are perfectly decent advise.
For me it really helps if I understand why I'm doing something, so if you like we can explain that as well.

Is your tank cycled?
Do you know why you need to do water changes? Like, what is the point?
(Just checking so that I don't write a really long but unnecessary post)

 

[Retrixy]

The other two answers are perfectly decent advise.
For me it really helps if I understand why I'm doing something, so if you like we can explain that as well.

Is your tank cycled?
Do you know why you need to do water changes? Like, what is the point?
(Just checking so that I don't write a really long but unnecessary post)

Yes my tank is cycled and yes I know how to do water changes. Water changes are to stop nitrates and nitrites and ammonia from rising.

 

[Murk]

Yes my tank is cycled and yes I know how to do water changes. Water changes are to stop nitrates and nitrites and ammonia from rising.

OK, cheers.
(Technicality: not to stop nitrites and ammonia from rising, because in a cycled tank those will be turned into nitrates).

So you do water changes to remove nitrates.
Nitrates are all in the water, so if you change 50% of the water, you remove 50% of the nitrates.
So, if you know what percentage of the nitrates is produced every week, you will also know how much water you'll have to remove every week.

Since you asked for an example:
Say you want to keep nitrates at 30ppm. So you measure the nitrates, they are at 30ppm, all good.
Then a week later you test again. Nitrates are now at 40ppm. If you now remove 25% of the water, you'll be back at 30 again.
If it's 60ppm instead, you'll know to do a 50% water change.
Makes sense, right?

Basically, every week you want to remove the nitrates that are produced. If your weekly production is 25%, change 25% of the water every week. If your weekly production is 40%, change 40%, etc.
If you feed regularly, weekly nitrate production should be relatively stable, so if you test for a few weeks you can get a good average.

Again though, the 20-50% from Binditheaxolotl and Calgarycoppers is a good estimate. If you don't want to go through the testing hassle, stick to their estimates

 

[Retrixy]

OK, cheers.
(Technicality: not to stop nitrites and ammonia from rising, because in a cycled tank those will be turned into nitrates).

So you do water changes to remove nitrates.
Nitrates are all in the water, so if you change 50% of the water, you remove 50% of the nitrates.
So, if you know what percentage of the nitrates is produced every week, you will also know how much water you'll have to remove every week.

Since you asked for an example:
Say you want to keep nitrates at 30ppm. So you measure the nitrates, they are at 30ppm, all good.
Then a week later you test again. Nitrates are now at 40ppm. If you now remove 25% of the water, you'll be back at 30 again.
If it's 60ppm instead, you'll know to do a 50% water change.
Makes sense, right?

Basically, every week you want to remove the nitrates that are produced. If your weekly production is 25%, change 25% of the water every week. If your weekly production is 40%, change 40%, etc.
If you feed regularly, weekly nitrate production should be relatively stable, so if you test for a few weeks you can get a good average.

Again though, the 20-50% from Binditheaxolotl and Calgarycoppers is a good estimate. If you don't want to go through the testing hassle, stick to their estimates

Alright, thanks!