watter change how much is too much?

[vantgE]

Hi I do a watter chaneg every week in mytank, but I heard something about not doing more than 30% I don't understand this really and considering I I drain the tank at least halfway plus the bottom half of the tank has more rock than watter. I see no problem doing this but wander if there is

 

[nc_nutcase]

The way I understand it changing more than 1/3 of the water raises your risk of temp, ph, etc fluctuation.

 

[Inchworm]

Hi vantgE

I don't see any problem at all with doing generous water changes. In fact I do them -- big and often-- myself. My fish love living in nice clean surroundings.

If you are concerned about losing beneficial bacteria, don't be. They are clinging to the surfaces of the filter media, gravel, plants, decorations and glass, and very few are actually free floating in the water.

On the positive side, substantial water changes remove buildup of nitrates and harmful bacteria which are actually living in the water.

 

[jflowers]

This is a good post

PFK magazine in the UK recommends little and often, as it reduces huge changes in temp, PH and others.

I change 10% every week in my FW tanks and 25% every other week in my SW tank, same with my brackish tanks.

Tanks that are stocked correctly and are filtered correctly shoud be ok with this, heavily stocked tanks, or tanks with unusually messy fish (CFC's tanks for example) will require much more.

I will watch this thread and change my regime accordingly

Jon

 

[Tokis-Phoenix]

I suppose it depends on what size tank you have and its conditions; small tanks it apppears tend to do better with small frequent water changes while larger tanks seem to do better with the large once a week water change.
If i am cleaning my filters out in my 3ft tank i only do a 30% water change but if not i do 40% one although i realy base how much water i take out on my water stats which i test weekly.

 

[jasmine]

I do 20% every fortnight on my trop and salt tanks

 

[iggy01]

I don't think there's a problem with big water changes.

Many people with heavily planted tanks do 50% weekly water changes.

 

[OohFeeshy]

I do 100% once a week on my 11 litre betta tank. It is filtered, but since I do large water changes, I'm not too bothered about loosing bacteria. Besides, it means I get the sand really clean and the amount of water is the same as my bucket holds.

 

[Tolak]

I think the problem occurs when people have a poorly maintained tank, no water changes for weeks on end. The fish become acclimated to the toxicity as well as the ph, which has probably changed. Do a 50% or more water change on a tank like this and you are adding water which is way different from what is in the tank, causing problems.

Large water changes should not be a problem in a well maintained tank. Discus breeders change anywhere from 30% to 50% every day or every other day.

I change 50% weekly in my tanks. I figure if I'm going through the trouble of breaking out wc gear, I may as well do a good job.

Tolak

 

[Synirr]

I do 100% water changes in all my betta bowls and 50% on my 10 and 5 gallons weekly. I figure the more fresh water the better... on the 29 gallon I basically just suction until I've gotten most of the poo off the bottom, which usually ends up being about 25% of the water