# Water Change Volume



## islanddave (Nov 6, 2012)

Hello All,


Simple question...............complex answer? I am about to purchase my mixing station containers and have a question regarding the volume of water changes. I know so much depends upon bioloads and individual tanks.........but as a general rule of thumb what is the suggested water volume (%) change for a mixed reef tank? Tank in question will be a 250 gallon.

Thanks Dave


----------



## PaulF757 (Dec 9, 2013)

I would think that a 50G drum which is a 20% water change should be enough.

I do 25% WC but only do them monthly.


----------



## sig (Dec 13, 2010)

there are no rules, because some people do not do WC at all, but I never seen how their tanks looks like.

I do approximately 10% weekly and I am using Reef crystal salt. This volume allows me to maintain good chemistry (Calc and Alk) with the current number of calk/Alk consuming corals

*100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3*


----------



## rburns24 (Jan 31, 2011)

sig said:


> there are no rules, because some people do not do WC at all, but I never seen how their tanks looks like.
> 
> I do approximately 10% weekly and I am using Reef crystal salt. This volume of allows me to maintain good chemistry (Calc and Alk) with the current number of calk/Alk consuming corals


-
I do 10% as well. Replenishes trace elements and helps by exporting a small amount of nutrients.
-


----------



## badmedicine (Oct 27, 2012)

As some more learned people have said, it depends on the tank status. It would appear that 10% per week is a good start. I personally do a once a month 25 gallon for 180 tank and it works for me.

Since the main purpose of the water change is to remove excessive wastes and to add new salt water based on the bioload of the tank, each tank is different.


----------



## fesso clown (Nov 15, 2011)

10% a week is pretty standard.


----------



## MPreston (Nov 11, 2013)

I am a 25 percenter a week due to bio load and tank set up. 

Keep in mind, every system is different. I run a 40 gallon, no sump with an underrated skimmer. High fish count/ bio load.
Large water changes is a must for me***


----------



## sweet ride (Nov 16, 2010)

20 gallons on a 110 gallon system every two weeks for me......


----------



## ohdino (Jun 17, 2014)

25-30% Monthly for my mixed reef.


----------



## explor3r (Mar 14, 2010)

I Always done 10% weekly in all my systems works like a charm...


----------



## fury165 (Aug 21, 2010)

~1.43% continuous water change daily (10% weekly).


----------



## Curtis22 (Dec 11, 2014)

I can vouch for not ever doing water changes (3 years) im highly against them seeing as i lose more than enough water to evaporation living downtown toronto its basically doing a water change daily if you are up to par on everything (unless you have a lid). I have no problem keeping nitrates at whatever i want from 0-2ppm.

Your going to have one of two problems. 
a) your nitrates are too high so your not able to feed your tank or keep an ultra low nutrient system propertly bc your skimming or cleaning is not up to par or your water flow/sump/filter is not up to par. Therefore do not be adding any amino acids which makes things worse or any supplements with aminos. 

b) your nitrates are 0 and too low, which is usually my problem but that just means you have to feed more to prevent bleaching and add amino acids. If you siphon your tank every day through a 200 micron filter sock it will clean your water, i wouldnt recommend throwing out your water ever. Siphon it into a buck or do what i do and just cut out the bottom of a plastic water pitcher/jug and put a larger filter sock into that and hang it in your sump. You can filter your tank through that sock for hours or all day long if you want .....while your clean your tank, the water just runs in your sump , you never even have to turn your pumps off ! 

 I dont know how if your doing a 20% water change the hell you have enough time to properly clean your tank - By the time you remove 20% of the water (which prolly takes 5 mins of syphoning) there is no way you cleaned your entire tank. I sit there and siphon my tank for 5-30 mins almost every day....i dont have to throw the water out to clean my tank !! its a rookie mistake if you ask me. Your gonna be paying money to get your phosphates to zero! Your going to be adding phosphates to your tank by adding tap water or doing water changes even if its 0ppm pure ultra filtered rodi water it has phosphate in it in toronto ! use the hanna ultra low phosphorous meter and check your rodi holding tank, it cant be zero unless your running your reactors in your top off water lol which makes no sense if your removing them from your tank anyways...

I just want to say you should get enough water loss from evaporation, maybe sometimes you also pull out cups of water for water testing daily, also once i month i chance my reactors (phosban and carbon) this loses lots of water when flushing new media out ! its basically a 5-10% water change once a month if your doing that !!! 

Anyways you might be water changing enough without knowing it depending how much top off water you have to add daily. I know i add over a bucket of of instant ocean filled with rodi water daily to my 180 gal system, proper siphoning is key to any tank, skimming, and amount of fish/feeding depends on your nitrates for your tank.

I truly believe water changes can only stress or kill or cause problems if done improperly or too large.

Your definetely better to do more small water changes than one big one.

Anyone doing a 25%+ water change suddenly is crazy if you ask me i couldnt imagine how many corals would die if i did that, but im sure some corals may like it (not sps) but it really depends if you have the A) or B) problem mentioned above ! 

You might have to do a 25% water change if your nitrates are through the roof or if you had a problem, death, or pumps go off too long to save your tank...but i would avoid doing them at all costs if you can keep your tank property there is no need.

anyways sorry had to express my hatred for water changes....feel free to come see my sps


----------



## loonie (Mar 29, 2008)

I did the same practice , not to change water since water is being replace daily due to evaporation. I had one major lost of fish due to high nitrate, now I do weekly water change of 10percent for my 100gal tank and I have no issues at all.


----------



## MPreston (Nov 11, 2013)

I am not a fan of doing a 25% on a weekly basis but my saving grace is that I only have a 40 gallon tank so the 10 gallons changed is "ok"

*** I make sure that I match the Alk, Cal, Mag, PH and temp to the best of my ability*** to eliminate stress

I wish I had the ability to not change the water or the volume in and out but without a sump I don't have the ability to syphon into the filter sock (awesome idea BTW) 

I, like Loonie have had lose due to high Nitrates, it is my own fault for not properly setting up the system beforehand, definitely regretting it now.
Another mistake was not syphoning the sand bed right from the beginning. Now, I am almost playing catch up** 

I do not run a SPS system at all (not one piece) all LPS so as mentioned every system is different. 

With a new system in the works- this will be strictly an SPS system and I hope that I can run the system as mentioned by Curtis as I have seen some BEAUTIFUL SPS dominate systems where they follow the same maintenance schedule as mentioned.


----------



## kies1 (Oct 8, 2009)

10 percent a week for me. I do two 5 gallon changes a week on my 90 gallon


----------



## Syed (Oct 20, 2010)

10% weekly is good. It just depends on the bioload in your tank and how much you dose or not at all.

I do 10 gallons on a 90 gallon tank every week.


----------



## kamal (Apr 21, 2009)

5g weekly change in a 25g so 20% only because I have a 5g bucket and it's what I am used to. I would ideally love to do small daily changes but I have no time for that and not got the appropriate setup to enable that to happen Easily or quickly.


----------



## jabeuy (Jun 4, 2014)

3g on my 30g (estimated volume), so 10%.

I also have a 7.5g that is barebottom and houses corals only. It's on my desk but I'm too lazy to do water changes on it so it gets 1g changed every 4-5 weeks lol. Brown algae all over the glass but the corals are doing alright


----------

