Recommended Water Changes?

[SeaDana]

From what I've read in the forums, everyone seems to have different recommendations for pwc's. What is the standard?

 

[Psybuster]

i guess standard would be 20% every 2 weeks, but i think it's too generic, cause everyone's situation is different. I do mine about every 1/2 - week, cause it's a new tank plus I adding more things to it. Once it's settled i think i'll switch to once every 2 weeks.

 

[mattrox]

25 - 30% once a week is a common recomendation.

 

[SeaDana]

I have been doing 10% once a week, 25% once a month. (I had read that more than 25% would be too shocking for fish, but people in the forums seem to do 50% quite frequently). What are your thoughts on this?

 

[Fishyfanatic]

I do about 25% weekly. But if the nitrates get high or I start to see algae, I'll bump that up to about 30% twice a week.

 

[Meredith]

I do 20% once a week. If I am feeling ambitious or if I have fed a messy veggie, I will do an extra small water change. something like 10% or so.

 

[rubysoho]

For beginners I would say 20% each week. Once someone is more experienced and can "read" their fish, then I believe they can use their own judgement. There are so many factors involved, it really is impossible to set a blanket rule.

 

[Jchillin]

David Baruchowitz, a reknown oscar keeper and editor of TFM, has advocated changing up to 90% of your water weekly. He has utilized a formula that shows that if you change only 30% of your water, you are leaving 70% of bad water behind. If this continues, you will never rid tank of all the bad water.

Of course, this is a drastic notion and flies in the face of the conventional amounts that most aquarists are used to. David did mention that this is not recommended for planted or immature tanks.

He actually demonstrated doing it in a large Oscar tank. There were at least 6 oscars in the tank. When the tank was left with about 10% in it, the Oscars were actually laying on their sides. When the new water went in, they immediately perked up and most, if not all of them stayed directly under the incoming water stream.

Pretty cool stuff.

Oh, I change 30% weekly in my 30 gal and once in awhile in my 75 planted.

 

[rubysoho]

wow, that is pretty cool though I can't imagine the fish being comfortable in such little water!! I would think that would stress them out beyond belief.

 

[greenmaji]

This really depends on the fish and how many you have but the rule I like to say the bigger the more often the better, to a point. I personly wouldnt change more then 80% daily.. normaly 50-75% weekly for me..

 

[Jchillin]

wow, that is pretty cool though I can't imagine the fish being comfortable in such little water!! I would think that would stress them out beyond belief.

That what I orginally thought until I saw that demo. I forgot to mention that David also metioned that this will also remove phermones from the water. Since we don't know a lot about what all of the properties the phermones contain (other than breeding or schooling) use caution in a community tank. It should have no affect at all in a species only, non-breeding tank.

 

[mattrox]

With Discus I did daily 30% pwcs. If I went away for a weekend I would to 80-90% change depending on the nitrate reading.

*Edit * This is a link to a pic of a >50% pwc in progress.
http://www.aquariumadvice.com/viewtopic.php?t=50074&start=20

 

[SeaDana]

Do you vaccuum every time you do a water change? How often do you all vaccuum?

 

[Fishyfanatic]

I vac at all water changes.