• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Frequent small water changes or weekly large?

Sam66

Member
Joined
6 Jan 2022
Messages
51
Location
Cambridgeshire, UK
Given a stable tank - 120l, heavily planted, no CO2, lightly stocked, ferts dosed daily

Ignoring the amount of work involved would it be better to change 10% of the water 5 days a week or 50% once a week?

Tap water is hard (Cambridgeshire) and treated with Prime.
 
Hi all,
I do about 25% twice (ish) a week, basically because it suits me better.
would it be better to change 10% of the water 5 days a week or 50% once a week?
I'm not sure it matters, but I usually change about 10% a day because it suits <"my morning routine"> of a black coffee, thinking about a cigarette and 20 minutes of contemplating <"the meaning of life"> (while changing the tank water).

I find a little <"uplifting music"> helps.



cheers Darrel
 
I'd just like to say 5 10% water changes isn't the same as a 50% water change. the same way two 50% water changes isn't a 100% water change.
personally, I have a lot of free time on the weekends, so i do a water change every week. around 50-60%.
 
Hi all,


I'm not sure it matters, but I usually change about 10% a day because it suits <"my morning routine"> of a black coffee, thinking about a cigarette and 20 minutes of contemplating <"the meaning of life"> (while changing the tank water).

I find a little <"uplifting music"> helps.



cheers Darrel


I do one weekly ~40% WC in both my tanks. Usually Saturday or Sunday. I make the RO water on Friday to let it sit to reach room temperature and degas for a day or so. If I had smaller tanks and butts of rainwater water sitting like Darrel I could imagine doing two smaller changes instead of just one big one. I got the whole procedure down so it really only takes me about 30 minutes per tank including cleanups and some trimming.
The key is never to allow maintenance to become a chore or a hassle.

Cheers,
Michael
 
Last edited:
Changing 10% daily will result in 52 percent total water changed in a week, so about the same volume as a 50% change once a week.

I'm not a mathematician, but I can plug numbers into calculators. Check out this one. Effective Water Change Calculator

I remember looking into setting up a continuous drip water change system, but I felt it was going to be too wasteful. To get to 100% you need to change a lot of water. I remember it was going to be something like 300 gal per week for a 40 gal tank
 
Changing 10% daily will result in 52 percent total water changed in a week, so about the same volume as a 50% change once a week.

I'm not a mathematician, but I can plug numbers into calculators. Check out this one. Effective Water Change Calculator

I remember looking into setting up a continuous drip water change system, but I felt it was going to be too wasteful. To get to 100% you need to change a lot of water. I remember it was going to be something like 300 gal per week for a 40 gal tank
That's a nice calculator, thanks for the link.

In order to change 50% of the water per week, dripping some water every second, you'd use 40% more water (so 20% of you tank's total water volume) than if you'd change it in one go.
So roughly 140l instead of 100l on a 200l aquarium.

Not too bad if you ask me. I'd do that for a small tank if it meant not ever having to worry about water changes.
Of course if your goal is to change 100% of the water with a continuous drip system then I wish you good luck ;)
 
Changing 10% daily will result in 52 percent total water changed in a week, so about the same volume as a 50% change once a week.

I'm not a mathematician, but I can plug numbers into calculators. Check out this one. Effective Water Change Calculator

I remember looking into setting up a continuous drip water change system, but I felt it was going to be too wasteful. To get to 100% you need to change a lot of water. I remember it was going to be something like 300 gal per week for a 40 gal tank
How would this work with IE dosing? When is the restart day (When we dilute existing ferts load with 50% fresh water)?
 
I would suggest 100% daily or more like continuous flow. That's what happens in natural systems... :)
 
I top the tanks up daily after removing any surface scum and so a weekly change on the large tank and sonetimes two on the smaller ones
 
Back
Top