water changes & how often - just seeing what everyone else does

10% weekly is good unless you have algae issues

 

I do 20% monthly / sometimes I do none for a few months...WC's arent like some think...it is not a requirement....
Danny

 

I do 10% when I feel like it. Maybe 1-2 times a month..

 

I do 35 gal on a total of 120 gal system every three weeks, plus the make up every other day.

 

10% weekly, usually on Sunday.

 

I do about 10% every week or two.

 

Once you're past cycle... are you still occasionally getting nitrite and/or ammonia readings? If you do, you have something else going on you ought to check into. You shouldn't really ever read any ammonia or nitrites again (for the vastly most part).

Sounds like your bacteria haven't caught up to your load... mini-cycles...

It's not a requirement *if* you compensate your minerals and don't have high nitrates, etc. You can't do nothing... but you are right that there is more than one way to go about things...

If you don't dose your Ca and Alk and your WC schedule is erratic, you will not have stable readings of your Ca and Alk (and Mg and pH, etc.)

I change 5 gallons (55 gallon system) roughly once every 5 months. I dose Ca and Alk daily and Mg monthly.

Trace minerals... I don't want to test for all of these and is the reason I still do the WC at 5 months (vs never).

 

I've been changing out roughly 5 gallons every 2 weeks on a 72g bow with a 20g sump. I just make sure my nitrates are down. I also dose with calcium

 

I do my tanks every 1-2 weeks with about 10%. I do periodic water testing and will adjust the frequency as needed. Much is dependent on the load and filtration used. I have a 90 gallon that can go for a good month without any changes and a 75 that needs to be changed out every week to 10 days.

 

I scanned through all the responses and it amazed me that everyone just gave a percent and time frame without stating what their bio load is and what type of filtration they have. Both of these are the important things to consider when determining how much, how often. Many are just doing water changes the way they are doing them because they were told to do it that way or because they think they have to. Those using a HOB type simple filter will inevitably have to do a somewhat larger volume change and more often. Those on the other end of the scale with more elaborate filtering systems will not have to employ the more rigorous changes. Evaporation is to be considered as many are toping off with fresh water at a rate from 1/2 gal. a day to up to 3-5 gal. That is a lot of fresh water being added. The amount of substrate and live rock are to be considered. The person who posted the question gave us no information as to the filtering capacity of the tank so our responses could be meaningless, inadequate or excessive for him/her.
So, the answer has to be based on that persons set up and if he/she cares to share that with us, a more appropriate answer can be given. For those responding, if they give their set up, their answer could then benefit others of the same set up.