Should I reduce water changes?

[Sharkbait19]

Hi,
For the longest time, I did weekly 20% water changes. As my tank reached stability, I reduced this to every other week. Then I upgraded my tank, and am now doing 15% weekly. Yet it feels like every time I do a water change, something goes wrong in my tank. Usually it’s just a ticked off coral or a diatom bloom. Most recently, a water change triggered the loss of my anemone and cleaner shrimp. So I’m starting to wonder—am I perhaps doing these water changes too frequently? I figured that this rate would help replenish certain elements that are consumed on a daily basis, but I feel like every time I do a water change, and the more often I do it, something either dies or reaches the brink of death. It’s becoming rather frustrating, and I feel like I need to change my approach to tank management. Any thoughts? How do you clean your tanks, and what else do you do to maintain stability?

 

[mcgullen]

As long as you are using trusted RO/DI water and salt, water changes shouldn't have those downsides. R u certain there is no other explanations for the animal losses?

 

[Dave1993]

i use to do a 5% water change every week on a 90 gallon had diatoms all over the sand ect now i do like 5% every 1 - 2 months diatoms are all gone

 

[Eagle_Steve]

Hi,
For the longest time, I did weekly 20% water changes. As my tank reached stability, I reduced this to every other week. Then I upgraded my tank, and am now doing 15% weekly. Yet it feels like every time I do a water change, something goes wrong in my tank. Usually it’s just a ticked off coral or a diatom bloom. Most recently, a water change triggered the loss of my anemone and cleaner shrimp. So I’m starting to wonder—am I perhaps doing these water changes too frequently? I figured that this rate would help replenish certain elements that are consumed on a daily basis, but I feel like every time I do a water change, and the more often I do it, something either dies or reaches the brink of death. It’s becoming rather frustrating, and I feel like I need to change my approach to tank management. Any thoughts? How do you clean your tanks, and what else do you do to maintain stability?

Water changes need to be based on reason for the change. Are you doing them to reduce nutrients? Replenish things? Or what?

When I did water changes, it was based on replenishment. I finally went to dosing, as i could replenish things slowly and a little at a time.

For nutrient reduction, you may want to do smaller ones, but more often. This will lead to less shock from a WC.

Also, when doing WC, I lke to let my SW mix for quite a while and try to match ph and temp to match exactly. This will also reduce stress from it.

Best place to start is to test the full run of things. Then test again in 3 days to see how much they dropped or raised. From there you can divide the difference by 3 and get your daily accumulation and consumption.

Once you have that, you can develop a path forward for nutrient reduction or replenishment of the other things.

 

[\m/reefsnmetal\m/]

Do you test you fresh mixed batches before the change? I never did and caused a huge alk swing when I went too long in between changes. I murdered all of my LPS/SPS. If you don't mix your salt dry before adding it to the water you could have an issue with settling. This would cause an out of balance concentration of elements that throws everything off when you do the change. Not saying this is the root of your issue, just a thought.

 

[X-37B]

I have done it all, weekly, monthly, two months, 3 months, no WC for 18 months.
I have settled on 10% once a month on my 3 systems.
Tank looks better after one.
I do it to remove the things that may build up in my systems that we cant test for.
In my 20g nano cube 2g's once a month helps as this system is pretty bare bones.

 

[Atrumblood]

I have done it all, weekly, monthly, two months, 3 months, no WC for 18 months.
I have settled on 10% once a month on my 3 systems.
Tank looks better after one.
I do it to remove the things that may build up in my systems that we cant test for.
In my 20g nano cube 2g's once a month helps as this system is pretty bare bones.

That sounds reasonable. I was a once a weeker for a long time. It makes me nervous going longer, but I just got done with a 4-week treatment of fluconazole which the instructions stated to not do a water change until the end of the treatment. After seeing my tank didn't spontaneously combust, AND some of my corals are looking healthier, I am now sold on once a month water change, and it saves a lot of salt.

 

[ReefGeezer]

Smaller, more frequent is better... less impact if the new water does not exactly match the old. I target 10% per week, but I'm lucky if I get it done more than 2 or 3 times a month.

 

[undermind]

@Sharkbait19 what is your process when you do a water change?

 

[Sharkbait19]

I first remove algae, which gets picked up by the filtration. Then I turn off the flow, and drain the water by about 15% (6 gallons). When the water is drained, I brush algae off of specific locations, such as corals, and change/clean filter media. Sometimes I stir the sandbed and pick up debris if the pistol shrimp didn’t do a great job that week. Then I fill a bucket with freshwater, adding reef crystals in accordance to volume. I mix thoroughly until I can clearly see the bottom. Finally, I slowly use a pitcher to raise the water level back to the appropriate amount, testing salinity along the way. I also use a turkey baster to blow any sand off of the corals/anemone.

 

[X-37B]

Hi,
For the longest time, I did weekly 20% water changes. As my tank reached stability, I reduced this to every other week. Then I upgraded my tank, and am now doing 15% weekly. Yet it feels like every time I do a water change, something goes wrong in my tank. Usually it’s just a ticked off coral or a diatom bloom. Most recently, a water change triggered the loss of my anemone and cleaner shrimp. So I’m starting to wonder—am I perhaps doing these water changes too frequently? I figured that this rate would help replenish certain elements that are consumed on a daily basis, but I feel like every time I do a water change, and the more often I do it, something either dies or reaches the brink of death. It’s becoming rather frustrating, and I feel like I need to change my approach to tank management. Any thoughts? How do you clean your tanks, and what else do you do to maintain stability?

As long as SG, temp, and alk are the same as the tank you should not have any issues. This has worked for me for 30+ years.

 

[DeniseAndy]

I am not a good one for this. Honestly, I do water changes when I can and when the tank looks like it needs it. Or, maybe I say, wait, how long has it been since doing one?
Now, caveat, My systems are very mature and have lots of things going for them in the nature of export and supplement. Algae scrubbers, CaRx, skimmers, etc. Most importantly, mine are softie, lps, clam systems, so they do not need the uptake of sps. I have a few sps, but nothing difficult.

So, what types of corals you have will dictate what needs to be done. sps, you will want to do more frequent, less amount water changes to replenish if you are not dosing.

Sorry you are seeing losses after water changes. I do 100% sometimes and have not had losses. Chekc the water you are changing and make sure to match pH, specific gravity and temp.

 

[DeniseAndy]

I first remove algae, which gets picked up by the filtration. Then I turn off the flow, and drain the water by about 15% (6 gallons). When the water is drained, I brush algae off of specific locations, such as corals, and change/clean filter media. Sometimes I stir the sandbed and pick up debris if the pistol shrimp didn’t do a great job that week. Then I fill a bucket with freshwater, adding reef crystals in accordance to volume. I mix thoroughly until I can clearly see the bottom. Finally, I slowly use a pitcher to raise the water level back to the appropriate amount, testing salinity along the way. I also use a turkey baster to blow any sand off of the corals/anemone.

Okay, I see issues here. You drain the tank and then clean the rocks and sandbed? No, no, do not do this. Clean the rocks and sandbed as you pull the water from the system or right before!
The saltwater should be made up 4-24 hours before you use it. Many salts need at least 12hours. Reef Crystals needs 12 hours to settle before using.

 

[Sharkbait19]

Okay, I see issues here. You drain the tank and then clean the rocks and sandbed? No, no, do not do this. Clean the rocks and sandbed as you pull the water from the system or right before!
The saltwater should be made up 4-24 hours before you use it. Many salts need at least 12hours. Reef Crystals needs 12 hours to settle before using.

Whoops, I misspoke there. I usually clean the sandbed, then drain. As far as mixing salt goes, should I start pre-mixing? I’ve heard of both methods, but am definitely willing to start pre-mixing if there are benefits, or if it is necessary.

 

[DeniseAndy]

Good to hear on the draining and cleaning. Yes, mix the salt the day before and add an airstone or pump to the bucket for movement and mixing.

 

[Pkunk35]

Hi,
For the longest time, I did weekly 20% water changes. As my tank reached stability, I reduced this to every other week. Then I upgraded my tank, and am now doing 15% weekly. Yet it feels like every time I do a water change, something goes wrong in my tank. Usually it’s just a ticked off coral or a diatom bloom. Most recently, a water change triggered the loss of my anemone and cleaner shrimp. So I’m starting to wonder—am I perhaps doing these water changes too frequently? I figured that this rate would help replenish certain elements that are consumed on a daily basis, but I feel like every time I do a water change, and the more often I do it, something either dies or reaches the brink of death. It’s becoming rather frustrating, and I feel like I need to change my approach to tank management. Any thoughts? How do you clean your tanks, and what else do you do to maintain stability?

I believe that nutrients can be affected by WC so if you ride the line of low nutrient then I think a WC can be a little destabilizing or if phosphate is a problem (meaning you can’t keep it in the system) then I feel as if one can bottom out their phosphate with aggressive WC schedule.

some questions:
What are your phosphate and nitrate levels? Do you have a lot of algae growth?
How do you know your WC killed the cleaner and nem? To me seems unlikely from WC.

btw I do 20%-25% weekly on both my nanos but have also done tanks where I did not change water for months and think age of tank and number of inhabitants/feeding habits and types of filtration all control the “proper” WC schedule.

I do change water with slightly different temps but I think salinity can change overnight with most salts because of incomplete mixing.

 

[PandorasChalk]

Before my dino outbreak I was having weird issues after my weekly 10% water changes. Figured out it was not pre-mixing the night before and not letting it come 100% to temp equal to the tank (I'd let it get to about 76 before dumping it in, tank was 78-79). Started mixing night before WC with a powerhead in the bucket and bringing it to temp and corals no longer got mad when the new water went in.

 

[Sharkbait19]

I believe that nutrients can be affected by WC so if you ride the line of low nutrient then I think a WC can be a little destabilizing or if phosphate is a problem (meaning you can’t keep it in the system) then I feel as if one can bottom out their phosphate with aggressive WC schedule.

some questions:
What are your phosphate and nitrate levels? Do you have a lot of algae growth?
How do you know your WC killed the cleaner and nem? To me seems unlikely from WC.

btw I do 20%-25% weekly on both my nanos but have also done tanks where I did not change water for months and think age of tank and number of inhabitants/feeding habits and types of filtration all control the “proper” WC schedule.

I’m not completely confident on the cleaner shrimp’s death, but the anemone went from beautiful to melted mess in a matter of days, and only started to look ticked after the water change. The shrimp’s death could be coincidental that it happened around the same time, but I like to try to find correlations and causation. I just ordered a new salifert kit because I’m finally sick of API, so I can get an accurate reading of phosphates and nitrates once that arrives. There has always been an abundance of algae growth, specifically green film algae.

 

[johnreef]

10% water change weekly are good for most of reef tank, i have performed 10% monthly since my nutreints are always in low range, i got normal bioload but bigger skimmer and huge refugium plus algae scraper, too clean of water(too low in nutreints) will cause the dino outbreak as well, water change will makes the dino goes even worse. people mess up the dino and diatoms sometimes as they looks similar to eachother, but dino are 100 times worse than diatom!!!

 

[mindme]

I don't do scheduled water changes and think they are a good bit a waste of money.

If you are using it for nutrient export, or to remove things in the tank, then it may help, but outside that - nope.