Aquarium Water Changes: Why do you "change" a percent of your water?

[revhtree]

Let me start off by saying that this isn't a question to debate the validity of "water changes." You either believe that changing out your water is beneficial or you don't. Whether it's reducing nutrients, metering salinity, replenishing beneficial trace elements etc, you believe it helps or it doesn't. Today I want to hear from those that DO change out their water and as to why they do it. Let's do it!

What's the main reasoning/reasons behind why you, personally, change out a percent of your water?

How often are you changing out a percent of your water?

 

[SashimiTurtle]

I can stay on top of dosing, having all my parameters as stable as I can get them, and over time of not doing water changes my tank will go downhill. If I keep up with water changes the tank remains healthy. I've tried "no water changes" several times, but those methods just do not work for me.

 

[Stoney]

I've been changing the standard 10% a week for trace elements but my icp tests are coming back more and more depleted so I'm starting to believe its not enough. Looking to try out DSR or reef moonshiners

 

[Koh23]

10% monthly so far works for me.

Of course, dosing ca,alk and mag.

Soft/lps tank, now i'm trying some sticks, all good for now...

I strongly believe that 10% change weekly reall cannot solve anything, its too small % to have any bigger impact, so, i dont do it.

But, if i do, trace elements will be primary reason

 

[Alexraptor]

Depends on the tank, my 15g skimmerless mixed reef gets about a 25-30% water change weekly. My two 25g tanks with skimmers gets 10% water changes bi-weekly.

 

[ReefGeezer]

I have gotten away from 10% weekly water changes but still do them sporadically. When I do them, it is because the tank looks "dull" i.e. the sand doesn't look as white, there is more visible bacterial mulm or other stuff on the rocks, the glass gets dirty faster, and corals just are not quite as plump as they might be. I usually do about 20% then. I am not sure why it corrects the "dull" problem, but it always does. I believe the positive response to be associated with the maintenance that occurs at that time, the addition of trace elements that I don't add otherwise, and possibly the reduction of DOC that my skimmer doesn't address. I have often wondered if the higher ORP of the freshly mixed salt water provides some short term benefit I just don't understand.

 

[vetteguy53081]

I change water 1-2x a year unless salinity climbs or fish are pouting

 

[i cant think]

I do it to remove harmful as well as replace and rebalance benificial nutrients for my Acros in my nano, in my 4’ tank it’s for my Euphyllia and other LPS. Here’s just two of my acros.

 

[Karen00]

I run the lowest of low tech tanks (no sump, skimmer, etc) so water changes are the only way for me to get rid of the old and refresh with the new as well as do a sand bed cleanup. I love how fresh and sparkly my tank looks after a water change and cleanup. I was doing weekly but now that I have added some sps corals I find I need to do twice weekly. I might need to start dosing soon.

Edit: I forgot to mention how much I change out... It's probably about 10% each time.

 

[njreefkeeper]

More than anything, I feel regular water changes help me stay ahead of anything that may be rearing its’ ugly head. I know many people with nice reef tanks that don’t perform water changes, but I have to say the tanks I admire most by and large so them regularly and it’s a much higher percentage path to long term success IMHO.

I also like that it puts me in tune with my tank. Certain acropora exhibit better coloration and polyp extension after a water change, whereas if I weren’t doing them I may have thought the colors and overall health was “good enough”.

 

[Glenner’sreef]

I “literally” enjoy doing a monthly water change on my 180g. Approximately 30 gallons each time. Reef Crystals. All of the above reasons are legitimate and if obtained then why not. Right? Without question, I feel my tank has a fresher, cleaner, crisper look than it did prior to the change. I dose B-Ionic and have a solid filtration system but there’s something about that clean fresh look that adds to my overall viewing pleasure.

 

[Karen00]

I change water 1-2x a year unless salinity climbs or fish are pouting

Wow!! That is amazing! Don't a lot of fish always look like they're pouting? LOL My gobies always looked ticked off. Haha. I keep telling them to "turn that frown upside down".

 

[vetteguy53081]

Wow!! That is amazing! Don't a lot of fish always look like they're pouting? LOL My gobies always looked ticked off. Haha. I keep telling them to "turn that frown upside down".

There’s a certain behavior in which you’ll know
I have 30+ fish and try to observe them as much as possible

 

[Karen00]

I have gotten away from 10% weekly water changes but still do them sporadically. When I do them, it is because the tank looks "dull" i.e. the sand doesn't look as white, there is more visible bacterial mulm or other stuff on the rocks, the glass gets dirty faster, and corals just are not quite as plump as they might be. I usually do about 20% then. I am not sure why it corrects the "dull" problem, but it always does. I believe the positive response to be associated with the maintenance that occurs at that time, the addition of trace elements that I don't add otherwise, and possibly the reduction of DOC that my skimmer doesn't address. I have often wondered if the higher ORP of the freshly mixed salt water provides some short term benefit I just don't understand.

I agree about the removal of DOCs. I don't have a skimmer (it's just a 5g) so I find after about four days the water is heavy with it which begins to accumulate on things so you're probably right that a skimmer still doesn't catch everything and a water change is the best way to clean out the system.

 

[Karen00]

There’s a certain behavior in which you’ll know
I have 30+ fish and try to observe them as much as possible

Oh yes. I agree. I give mine a hard eyeball everyday and I'm absolutely sure our fish let us know when they're not happy.

 

[Mschmidt]

I said other: because the internet said I should. But also to keep other levels stable.

 

[Wiskey]

I honestly don't know why I do it. I know full well that even a monthly 20% water change does little to keep levels where they should be, regardless if they are too low or two high. But! It has to be better than not trying.

I try to dose trace elements, first with Core 7, now moving toward the Baling Method with TM Part C and the TM A and K. I do the very occasional ICP test to make sure I'm in a good range there.

So my 15% water change every 2 months is probably useless. It's my security blanket.

 

[LSU-reefer]

I mainly use it as a maintenance opportunity. It gives me a chance to remove the water and clean equipment, sump, fuge, etc. While I'm doing that might as well through some fresh water at it.

I do notice the tank "appears" to do better the first few weeks after a water change. I do mine monthly and about 20-25%

 

[rtparty]

If I change water it is to remove organic and inorganic things we can't test for. This is the ONLY benefit water changes actually have (for standard tanks and standard amounts i.e. 10% weekly. A 5g nano is super easy to do 50% changes weekly and is an outlier in the hobby.)

 

[livinlifeinBKK]

I change water weekly to replenish trace elements for my corals as well as to remove some built up DOM in two of my tanks