Water changes- When and how often?

[vetteguy53081]

There has been many reefers and new reefers asking, either:
When should I do my first water change, and others asking how much water should I change?
Not changing water can lead to tank health issues, algae and cloudy tanks, yet mano of us don't change water at all and our tanks do well.
I went 5 years without water changes and then in December attended a couple of seminars that weighed the pros and cons of doing and not doing water changes. I resorted to daily 2 gallon water changes in which I actually witnessed coral growth and vibrant colors. In part was due to replenishment of trace elements and being the best task for keeping good water quality and water parameters.

What percentage are you changing water and how frequently and on what size tank?
What benefits are you seeing with changing water regularly or not at all?

 

[EricR]

Previously, I was doing 20%-25% every other week or at least twice per month.
Some months ago switched to about 10% weekly.

Honestly, the only difference is that my sand bed doesn't get as dingy since I vacuum it as my water change (so now that gets done more often).
*other than that, no appreciable difference noticed

 

[Reefer Matt Verified Media Partner]

Depends on nitrates for me. From 2 weeks to a month on 5 different tanks.

 

[chthao]

when my corals tells me

 

[KStatefan]

I do 10% per week with an auto water change system that runs multiple times per day.

 

[fodsod]

I typically do a 10ish% every 10-12 days on both tanks. My parameters seem to stay more stable with this schedule verses shorter or longer intervals. If there's an issue of some kind then I'll do changes as needed of course.

 

[bushdoc]

I tried them all:

• no water changes at all ( did work well for few months, but not much longer),
• AWC ( I was running it for few years, but equipment issues caused me to abort it)
• Weekly-to much fuzz and my work schedule was top busy, also was it really necessary?
• Now I am doing it every 3-4 weeks and both fish and coral seem to be OK with it.

I test for Nitrates and phosphates weekly and change my approach according to the results

 

[Eagle_Steve]

180 tank w/ 50g sump.

100% every week via AWC and then about 40 gallons when I clean sump, skimmer, and scrubber every 1.5-2 months.

Benefits, heavy in, so heavy out keeps me where I want to be. In addition, I consume about 3.8-4 DKH per day, so helps with amount of things that need to be dosed and how much has to be dosed lol..

 

[shakacuz]

running the reefmoonshiner method. 0 water changes since the tank has been running (feb 2021)

 

[gbroadbridge]

About 10% once a month.

Sometimes I go 2-3 months with no problems.

I am dosing trace elements as well as Nitrate/Phosphate so that they don't bottom out.

 

[Alexraptor]

As often as is needed.

Something I've learned in the past 18 years, is that not every system is the same. They all have their unique quirks and needs, and entirely own balance depending on stocking and microorganisms.

My 15-gallon reef needs weekly 30% water changes to stay on top of the nuisance algae.

My old 25 can go months on end without a single drop of water being replaced, simply by virtue of skimming and binding up excess nutrients in biomass (benign clove polyps). For that tank I tend to perform a series of large scale. 50%, water changes once a year, to balance out any parameters that have been drifting.

 

[AKL1950]

This may sound a little over the top, but I guess we each have our own philosophy of how to emulate what happens in a natural reef. My spin is to try to match nature. In that respect, the reefs in the ocean receive two water changes daily from the lunar tides And constant change from the world ocean currents. New water, elements and nutrients flows in and old junk is pulled out. It may not be necessary for our tiny reefs, but that's what drives me to do daily water changes. If you have a stagnant body of water in nature, saltwater or fresh water, that does not receive new water and can’t dispose of old water, at some point that ecosystem system will become stagnant. Flowing streams are always cleaner than isolated ponds that build up with algae. For saltwater, If you have ever been in Izmir Turkey, you would know to never get into the water in Izmir Bay. It is connected to the Mediterranean, but it’s a landlocked bay and that prevents the tides from circulating the water in and out of the bay. Every disease known to man is in that bay. Stagnant water is not good for life.

For my 180 gallon system, I do 2 gallons per day set up through Apex using a doser.

 

[NkSde]

Usually do about 30% monthly
Nothing showing any signs of deficiencies. No coral yet tho

 

[vetteguy53081]

This may sound a little over the top, but I guess we each have our own philosophy of how to emulate what happens in a natural reef. My spin is to try to match nature. In that respect, the reefs in the ocean receive two water changes daily from the lunar tides And constant change from the world ocean currents. New water, elements and nutrients flows in and old junk is pulled out. It may not be necessary for our tiny reefs, but that's what drives me to do daily water changes. If you have a stagnant body of water in nature, saltwater or fresh water, that does not receive new water and can’t dispose of old water, at some point that ecosystem system will become stagnant. Flowing streams are always cleaner than isolated ponds that build up with algae. For saltwater, If you have ever been in Izmir Turkey, you would know to never get into the water in Izmir Bay. It is connected to the Mediterranean, but it’s a landlocked bay and that prevents the tides from circulating the water in and out of the bay. Every disease known to man is in that bay. Stagnant water is not good for life.

For my 180 gallon system, I do 2 gallons per day set up through Apex using a doser.

Not over the top. Everyone has their method and reasoning and with many new reefers joining and starting up, this thread shows many a method and reasoning for changing water and why or why not, they do water changes.

 

[danenelsen]

I do 10% weekly.

No coral yet, but I figured I'd get into the good habit of water changes anyways.

 

[dstockwell]

20% every couple of months, no set schedule.

 

[Cichlid Dad]

25 gallons on a 110 system every 2 weeks

 

[Obdoc63]

I've recently started doing a 5 gallon change every week when I remember.

 

[00W]

10% every Monday morning.

 

[Victay]

I think it would be really helpfull if people state what size tank they have when they talk about the size and schedule of their water changes. A 100% water change on a 10g tank is a bit different to a 100% water change on a 120g tank or on even larger systems IMO.