Whats Best With Water Changes?

[Tetraking]

Hi all, just wondering what your thoughts are about water changes, is it best to do lots of little ones, 10% 3 or 4 times a week or do two 15/20ish % changes a week, my fish are looking great lately and athough i have not really been recording when i change water recently i have been getting urges to do something with the tank ( i will not rearrange this time round lol), so to combat my urges to mess to much with the set-up and seen to do water changes instead, i must be doing a water change of about 10% every couple of days, is this a bad thing? i have a lot of plant now and if i left it a week i think the water would go yellowish.

 

[Jazzzz]

Hi all, just wondering what your thoughts are about water changes, is it best to do lots of little ones, 10% 3 or 4 times a week or do two 15/20ish % changes a week, my fish are looking great lately and athough i have not really been recording when i change water recently i have been getting urges to do something with the tank ( i will not rearrange this time round lol), so to combat my urges to mess to much with the set-up and seen to do water changes instead, i must be doing a water change of about 10% every couple of days, is this a bad thing? i have a lot of plant now and if i left it a week i think the water would go yellowish.

I do the same thing in my little tank because its satisfying and very easy, I was going to ask the same question

 

[Tetraking]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

 

[rocknurworld2006]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

 

[invader]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

Not necessarily! Depends on your stocking levels and the type of fish. You really can't do too many water changes, imo. And honestly, I've never done a water change as small as 10% on my tanks ever. I do huge ones, 75%, sometimes.

 

[rocknurworld2006]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

Not necessarily! Depends on your stocking levels and the type of fish. You really can't do too many water changes, imo. And honestly, I've never done a water change as small as 10% on my tanks ever. I do huge ones, 75%, sometimes.

personally 75% is far too much!!!

 

[tenohfive]

I do alternate 20 and 40% water changes every 2-3 days, and I notice my community tank seems unhappy if I leave it beyond 4 days without doing any water changes.

I wouldn't go the the extend of 75% water changes unless there was a very good reason to - but I don't see any harm in 10% every couple of days.

 

[invader]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

Not necessarily! Depends on your stocking levels and the type of fish. You really can't do too many water changes, imo. And honestly, I've never done a water change as small as 10% on my tanks ever. I do huge ones, 75%, sometimes.

personally 75% is far too much!!!

One question: Why?

 

[backtotropical]

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

personally 75% is far too much!!!

Can you give us a reason for that Rocknurworld? Why is 10% ok, but 75% too much?

Your thoughts on water changes are an unfortunate rumour in the hobby which contributes to the demise of 1000's of fish. Actually, water changes of any size will have no negative effect so long as a few things are considered.

The first is the temperature of the water. This should not be dramatically changed quickly as it can stress the fish, however in practice, anything up to around a 50% change straight from the tap shouldn't move the tank temperature too much anyway. Fish aren't as fragile as many aquarists think. They actually suffer quite rapid temperature changes in their natural habitat, and theres really no need to 'wrap them in cotton wool' in the aquarium environment. If you are performing large changes and think that your water change will drop the temperature too much, all you need to do is pre-heat the water slightly.

The second consideration is pH. Large rapid pH fluctuations can stress fish, but if water changes are performed regularly, the tank pH will remain roughly the same as the tap pH anyway. You only really need consider this when the tank has went without a water change for a long time or if the replacement water has a drastically different pH to the tank water, which is not usually the case.

The third thing to consider is hardness. Hardness fluctuations are actually considered to be much worse for fish than pH fluctuations, and many deaths which are attributed to pH fluctuations, will actually have occurred due to hardness fluctuations instead. As with pH, assuming that regular maintenance is carried out, the hardness of the tank water will always be close to the hardness of the tap water, so it usually doesn't need to be considered.

The fourth and final thing is chlorine / chloramine. The vast majority of municipal water supplies will contain one or both of these. All replacement water should always be properly dechlorinated to be safe.

Of these four considerations, two take care of themselves so long as regular water changes are maintained, so in effect the only things that most people need to consider are dechlorination and temperature. If these are considered and the relevant steps taken, no water change is too large, not even 100%.

The only situation where large water changes would have a negative effect are if the above considerations are not taken into account, or if the tank has went a long time unmaintained (Old Tank Syndrome).

I would like to hear your thoughts on why 75% is too much. Water changes of that size may not always be 'required', but that is another discussion altogether.

Tetraking, in answer to your original question, weekly water changes are fine, as are daily water changes. Most people base their regime around their other commitments, and do what they can. Small frequent water changes are probably slightly better as it will keep the water parameters in the tank more constant, but for most of us, the benefit of doing daily changes as opposed to weekly changes is probably negligable.

You should also be aware that for instance, 2 x 50% changes is only equal to 1 x 75% change, not 1 x 100% as many people think. It actually takes between 6 - 7 x 10% changes to change the same amount of water as 1 x 50%. This in itself makes daily / bi-daily changes lots of work for not much benefit (usually). Frequent water changes certainly won't do any harm as i have described above, but we also must weigh up the effort involved and the cost to the environment against the potential benefits.

Hope this helps you.

Cheers

BTT

 

[shortymet55]

You should also be aware that for instance, 2 x 50% changes is only equal to 1 x 75% change, not 1 x 100% as many people think. It actually takes between 6 - 7 x 10% changes to change the same amount of water as 1 x 50%. This in itself makes daily / bi-daily changes lots of work for not much benefit (usually). Frequent water changes certainly won't do any harm as i have described above, but we also must weigh up the effort involved and the cost to the environment against the potential benefits.

Good point. Remember when you do a water change one day, then another the next, your going to be removing some of the new water of the previous day.

 

[waterdrop]

I'll just throw in my 2 cents to say that having done a lot of searches and a lot of reading on water changes in the last few months, I'd say that everything BTT says up there is backed up in a lot of the things I read. Really a very nice summary he put together there.

~~waterdrop~~

 

[Gatorbait]

My tank is 25gl, i sould have mentioned this before, i suppose it is quite small, the smaller the tank the more you have to change water, this seems to be best advice, am i changing it to often, will i harm the eco stuff going on in my tank by doing so. You are right razzz it is kind of satisfying

you should do 10% weekly ONCE or 20% fortnightly ONCE. more than this is a bit too much

Not necessarily! Depends on your stocking levels and the type of fish. You really can't do too many water changes, imo. And honestly, I've never done a water change as small as 10% on my tanks ever. I do huge ones, 75%, sometimes.

personally 75% is far too much!!!

I disagree and would like to know why you say this.

You're throwing this info out there as a generalization without knowing any facts such as stocking levels, type of fish, feeding routine, tank size etc.

In a perfect world it would be best if fish had 100% new water every day, so I'd like to hear why you think a 75% wc is too much.

You state that anything more than 10% once a week or 20% every 2 weeks is too much. I keep piranhas and they would eventually die with such little water changes. You don't take into consideration for mass and bioload of tank inhabitants?

 

[invader]

You state that anything more than 10% once a week or 20% every 2 weeks is too much. I keep piranhas and they would eventually die with such little water changes. You don't take into consideration for mass and bioload of tank inhabitants?

I totally agree with you, Gatorbait. The fish that I keep would eventually die from poor water quality if I only changed 10% a week. I keep horribly messy, large fish that require the maintenance of large water changes.

rocknurworld2006, you are generalizing too much when it comes to keeping fish. You have to take in consideration that not everyone keeps tetras and general community fish that don't create that much waste. BTT gave some really great advice when it comes to water changes that I suggest you read up on.

 

[tangokitty]

I was just wondering what all of you do with that water after you change it? I use my water to water all the patio plants that way I am recycling it, since I live in CA and we are in a bad drought.

 

[invader]

I was just wondering what all of you do with that water after you change it? I use my water to water all the patio plants that way I am recycling it, since I live in CA and we are in a bad drought.

Since I use a python, all of my water goes outside and into the grass. If I'm ever using a bucket, it goes to the plants on the patio (like you) or in a bush or something. No reason to waste it.