Water Change Frequency

[JustKia]

OK I know at least a handful of people will jump and say they do x% water changes religiously every n days.
How often to you do your water changes?
How many do water changes based on stats?

Since my 125L tank completed cycling I've done in the region of 3 water changes of around 25%. My water stats show 0 for ammonia and nitrItes and ~30-40 for nitrAtes (~30 from tap). I've got lots of plants in there, quite a variety (eloda - apparentlyhas mild antibacterial properties and since planting it I have had perfectly clean sand, before I had small areas of grey/green/bluish sand); ludwigia repens; baccopa monnerii; wisteria; cabomba; spiral and long vallis; frogbit; anubias (barteri, I think); tiger lotus; nymphaea rubra; java moss; marimo moss balls and another unknown plant).
Mother nature has successfully raised 2 Endler fry and a cory fry (obviously 1 egg that didn't get eaten). The fry have not only survived but thrived (no liquifry or any fry food given), regular tropical granule (mix of coarse and fine) and frozen foods given sometimes once a day sometimes every other day. I thought I'd have problems not feeding my fish, but to be honest, seeing how well they all look I have no problems letting them have "no food days". I'll usually feed morning on day 1, evening on day 2 and not at all on day 3 (so it's around every 36 hours-ish that they get fed).
The water looks crystal clear. The substrate is clean.
It's fascinating to see plant matter (such as a fallen leaf) completely disappear within a couple of days. The circulation is quite effective and can be seen by the effects on the substrate - trails left by MTS are swept over in less than a minute, all the little dapples from the corys rootling around vanish and a natural undulation has occured.
With the lights, moonlights and air pump on timers; and a fluval 405 external filter it's like a mini eco system requiring very little intervention from me.

I know some are going to tell me I should be doing weekly changes, etc and if that works for you fine, but I'm a seeeing is believing kind of girl and what I'm seeing is working =)

 

[Truck]

50% every week on a wednesday although im currently riding out a nitrite spike with 3*75% changes a day with buckets

i must have had a freak die off

i test once a week (good job i spotted the spike!) and act accordingly

 

[fatheadminnow]

I am only home from school on the weekends.

When I come home, I check the levels, and based on my findings do a X% water change.

-FHM

 

[dcarmor927]

I do 25-50% every monday, depending on the readins and i test every two or three days

 

[stang1]

My bigger tanks and the smaller mature ones get 20% water changes every two weeks.
The smaller tanks that have only been running a while get 20% water changes weekly.
I only test the water if I think there is a problem.

 

[drobbyb]

I do 50% a week. Sometimes I might go 8 or 9 days.

 

[Gilli]

I do a 30% water change and vac religiously every week although not always on the same day.

 

[BigC]

15 litres/weekly in 70ltr tank

 

[backtotropical]

I change 50% every week regardless of stats. I only test if I see any other indication of a problem.

Justkia, fish need certain minerals in their water to help with osmoregulation (the reason why fish won't last long in pure RO water). These minerals are present in sufficient quantities in tap water, however are slowly used up by the fish. These essential minerals are replenished by water changes, so in a well maintained tank, it is never an issue. In a tank which doesn't receive any water changes, these minerals will deplete to dangerous levels, and could potentially lead to health problems and / or death.

So, whilst nitrate level might be the only 'visible' reason for water changes, and your method might appear ok from your aquarium test kit results, there are other issues which may arise unexpectedly.

Tanks can be kept without water changes, but this is usually heavily planted tanks with no (or very few) fish, or tanks with additional equipment running them other than your standard aquarium filter.

I have never heard of a domestic setup which receives no water changes being an ongoing success. They always come across problems sooner or later.

However, that said, you are performing some water changes, and as long as you change enough water to replenish essential minerals and prevent Old Tank Syndrome setting in, I foresee no problems. It is important to realise that it can be easy to let the tank slip into a state of disrepair if water changes are infrequent. Some have claimed success, but many more have run into problems.

Cheers

BTT

 

[doresy]

Community and Betta tanks get 30% change every 7-10 days. The Tanganyikan set up gets 15-25% every 6-7 days

 

[bitteraspects]

Anything less then 25-30% weekly is poor husbandry. If someone can't make time AT LEAST once a week to make sure their fish arent swimming in their own waste, then they have no business keeping fish imo.

 

[stang1]

I have to disagree bitteraspects.
My fish are my hobby and my job and they are all well cared for. I haven't had any fish deaths in a very long time and they are all thriving.
All my tanks are overfiltered and my bigger tanks run two externals. On the odd occasion when I have checked water stats, the readings come back perfectly fine.
Please don't assume that people don't care about their fish just because they are not doing weekly regimes.

 

[matchstickman47]

i wouldnt say i do a certian amount ... just what looks good and enought to get all the poo from the bottom

 

[bitteraspects]

I have to disagree bitteraspects.
My fish are my hobby and my job and they are all well cared for. I haven't had any fish deaths in a very long time and they are all thriving.
All my tanks are overfiltered and my bigger tanks run two externals. On the odd occasion when I have checked water stats, the readings come back perfectly fine.
Please don't assume that people don't care about their fish just because they are not doing weekly regimes.

maybe you should spend a week swimming in your toilet, and see if you dont change your mind.

 

[stang1]

I will quite happily post my water stats to assure you that my fish are all fine.
As I said, my tanks are all over filtered and my readings are absolutely fine.
Maybe you shouldn't judge people without knowing anything about them.