Water Changes: Where do you stand on water changes for your reef tank?

[revhtree Verified Admin]

Pretty simple today. I think it's been a while for a site-wide poll on water changes so let's do it! Let's talk about water changes and where you stand concerning your tank!

1. How often do you "change out your water" in your reef tank, what percent and how many gallons is your system? Or do you even?

2. How important or not important do you think water changes are for your reef tank?


@CMO no water change reef! Thread here.

 

[jeeperreefer]

i have a small 20 gallon long with no skimmer so water changes are a must for me to control nutrients.

 

[sixty_reefer]

I was never able to control nutrients in mine with water changes, I do try and keep up with it mainly to replace trace.

 

[andrewkw]

I do an 8-12% water change every single week. I believe I've missed one week in the last 3 and a half years. The slight variation in amount is mostly if I see more detritus then usual or plan on blowing under my rocks more then a usual week. I like to save 80-90% of this water and reuse the water on my other tanks. Prior to this I was not as religious about water changes and did larger by weekly or even monthly water changes. I do have a nano tank that only gets very occasional water changes so this is not a one size fits all approach even in my own home.

IE main display gets fresh saltwater even though I don't need to change the water but various other tanks that may actually need water changes get the used water which is closer to their parameters then freshly mixed IO.

Almost as important as the water change itself is it gives me an opportunity to target feed. I turn off all pumps including return for approximately 1 hour a week for target feeding. This also gives me a chance to observe corals up close, find anything that got knocked over ect.

 

[WVNed]

I have done 10-30% a week, 20 % a month and none for months.

Now I do 1% a day. This seems to be working the best of everything I have tried.

 

[DaneGer21]

I do weekly changes. Usually every Sunday morning. That’s my “me” before everyone else wakes up. I change anywhere from 20-40gals depends on how or what I’m cleaning. Roughly 10-15%’ish weekly.

I have a few large tangs, and a minimal aquascape, so my “filtration” is on the light side. My nutrients can climb fast without my weekly intervention.

 

[Lasse]

1. How often do you "change out your water" in your reef tank and what percent? Or do you even?

2. How important or not important do you think water changes are for your reef tank?

1) never if it is not an issue
2) Could be important if it is an issue - other times - not important for MY tank

Correct myself - i run Triton Core 7 and have to compensate for elevated salinity with around 0.65 L a day - it means around 0.2 % WC a day


Sincerely Lasse

 

[phatduckk]

I recently setup auto water changes using the Dos. It’s loud enough to be noticeable and every time I hear it kick in I think “that’s amazing”.

My reefer 350 has about 75g of water & I have the AWC do 1% / day.


...

 

[Chrille26]

I do weekly water changes of 10 to 15%. Not so much because I need to replace trace elements, since I dose 2part, or reduce nutrients since I run a refugium, skimmer and other bio media, but because I like to vaccum my rocks and sand of detritus and buildup.
I also use the siphon to pull out and remove unwanted algae and slime.
I also like to think the fishes appreciate the new fresh, clearer water but thats just my personal thought. :)

 

[jda]

I try and do 15-20% a month, but do not freak out if I miss one every once in a while.

For me, there is nothing cheaper or more effective. 200 gallons of water change for $40-45 of salt... plus some DI costs. People spend 10x this buying supplements and other things to avoid them and say that it is all cost related, but it is laziness most of the time. At $10-12 for a 20% water change, there is nothing cheaper to remove the bad and put in some good.

 

[crimper]

10% WC every other week here just for the Trace here.

 

[Vette67]

1). I do a 35 gallon monthly water change, which is about 10% a month.

2). I use the water change as an opportunity to vacuum detritus out of my sump and my BB 75. I went for years without doing a water change and then had a pretty bad GHA crash in 2012. Since then, I’ve been more diligent with water changes.

 

[ApoIsland]

1. How often do you "change out your water" in your reef tank, what percent and how many gallons is your system? Or do you even?

2. How important or not important do you think water changes are for your reef tank?

1. I do one large water change per month. 120g display with 40g sump but only about 130g total water volume. change approx 40-60% (55-75g) per month depending on how much I feed and how frequent the glass cleanings need to be the week of the WC. Have been doing this for the last 6 years. My first 4-5 years I was doing weekly as I had a smaller tank and also really didn’t know what I was doing :)

2. I do not have any mechanical filtration and don’t dose so the water changes are very important for nutrient export and to replenish elements. If I miss a month the blue tang and yellow tang will usually get ich and the sps will lose their white growth rings/tips.

 

[blstravler]

I have a Red Sea 425xl - so about 100 gal total volume. I do a 1/2 gallon (.5 %) water change every day via AWC. This changes about 15% a month. I’ve just set up the AWC and might go to one gallon every day but for now everything seems happy. I was never a fan of water changes but every time I did one I really noticed improvement in the ‘happiness’ of everything so this is the reason I went with AWC. I’m sure it also will help control No3 and Po3 which is a nice bonus.

 

[Lasse]

I see a argue for WC here (and everywhere else) that it is good for replenish elements. I think that trace elements is very important for a good reef aquarium - but I can´t see how you can guarantee it with WC and commercial synthetic salt mixtures. Please explain that for me

MVH Lasse

 

[K7BMG]

I would say, maybe to a fault I am not a scheduled WC person.
I do WC when I see or feel its time.
My tank is growing, water is clear, and lightly loaded in compairison to the majority.
I had a dos set up for this but I have rearanged stuff and not put it back.
Now I am rebuilding my RO/DI with larger storrage tanks.
I use my RO/DI storrage tank as my ATO reservoir as well.

When I do a large water change I also use a pump to blow off the rock and stir up the crushed coral.

 

[725196]

To me, water changes are essential to a healthy reef. No matter what elements you add and no matter what mechanical/biological filtration you use. Nothing will ever beat taking used/spent water out and adding fresh, properly mixed water back to your tank. With such a small volume of water, no matter how big the tank, we will never have the standoff the ocean.

On a side note, I test all of the water from my mixing station BEFORE it ever goes into my tank. I want to make sure the parameters are where I want them to be.It is easier to make corrections before you put it in the tank and may just save the lives of your aquarium inhabitants.

 

[gabrieltackitt]

1. How often do you "change out your water" in your reef tank, what percent and how many gallons is your system? Or do you even?

2. How important or not important do you think water changes are for your reef tank?

1. I do 10% every week if possible or two weeks if not. Totals about 5 gallons of my 50 gallon system.

2. Currently I don’t dose anything so WC are fairly important in keeping the levels of everything correct.

 

[LxHowler]

I do weekly 10% weekly, I have started to do less now that I am doising but I still do it most weeks. Used to do religious weekly changes to replenish all trace elements and maintain levels. 30gallon mixed reef system with mostly frags, don't use to many elements at the the minute so weekly changes can still just about maintain stable levels.

 

[LavalReefer]

1. I was doing 10% every week but I upgraded to an oversized skimmer and with only 7 small fish (1inch) in 100g, it was a little too much, so I am considering every 2 to 4 weeks maybe. I still have to find the right rhythm.

2. I think it's important especially when the nutrient export is not excellent. If there is low nitrates and phosphates, then maybe not so frequently. I think dosing is enough with occasional water changes.