water changes

richard01

New Member
i have been into tropical fish forty years plus. do water changes hurt fish ? it depends. how much, how offten. lets say, your tank is cured, it has its own chemistry. when you water change, your adding mars to earth. your adding green salt water to cured salt water. to put it simple, like eating a raw carrot, to a cooked carrot. i do only a five percent water change every two, to three weeks. ammonia, is the main fish killer, nitrates, nitrites, are always there, no matter what you do. you can't do enough water changes to get rid of them. plus, you'll change your chemistry so much, your fish will stress out, and die. yes, water changes will kill fish, if done to much. remember, your fish lay in their bed, if you disturb their bed to much, they can't adjust, and will die. well, hope this helps people. i learned the hard way. $300.00 worth of fish. salt water. CHOW !
 

pegasus

Well-Known Member
Welcome to the forum, Richard. Not really sure why tropical fish are part of the discussion, as this is a saltwater forum. I, like you, spent decades raising tropical fish. Saltwater fish is a completely different hobby. I've never lost a fish due to a water change, be it a big or small change. I've gone as far as to change 100% with no casualties. How? Slow acclimation. People do it all the time when they bring a new fish home, or have to send a sick fish to the quarantine tank. Perhaps it's true that ammonia, nitrite, and nitrate are present in freshwater, but those are not acceptable in saltwater. With proper amounts of live rock and live sand, there will be NO ammonia or nitrite, and with an adequate sand bed and adequate filtration, there will be little to no nitrate. My ammonia is 0, nitrite 0, and nitrate 0.5 ppm. Oh... and I change 25 gallons out of 140 gallons once a month... or two. Not because of ammonia, nitrite, or nitrate, but only to replace trace minerals. I certainly don't change that small amount due to a fear of losing fish, but simply because I don't have to. As long as salinity, pH, and temperature of the new water is the same as the tank water, there will be no adverse effect on the livestock in the tank. A steep, sudden increase in salinity will kill fish. A sudden swing in pH will kill fish. A sudden change in temperature will stress fish, and I suppose if the change was too great, it could possibly kill fish.

Adding fresh water to the tank is more like adding fresh cooked carrots to your old cooked carrots. It freshens the batch. Just my 2c...
 

flower

Well-Known Member
Hi welcome to the site!
I also kept freshwater fish for 30+ years, before going saltwater. Pegasus is correct, it's a whole different world. You can indeed overcome nitrites and nitrates in a freshwater system, and I have never in my life killed a fish doing water changes. I even have emptied out the entire tank, put my freshwater fish into buckets and washed everything down, and they never hiccupped that anything was wrong. So whatever you did doing your water change, contaminated something perhaps...it wasn't the basic water change that caused your problem.

In all the years of keeping saltwater fish, I never lost a fish doing a water change, and with using macroalgae now, and back when I kept corals, an Aquaripure nitrate filter, + GFO reactor, I don't/didn't have a problem with phosphates, nitrites or nitrates either, let alone ammonia. You should share how your system is set up, maybe we can help you.
 
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flower

Well-Known Member
I did 10% water change weekly, and add top of water daily. What did I missing?
Hi,
What kind of water did you top off with, RO (reverse Osmosis) or tap water?
What kind of container did you use to hold your water...mixed and fresh before mixing?
How long did you churn the new mixed saltwater before you used it?

There are lots of reasons you can do damage during top off or water changes. It isn't the change out that is the problem, there is something wrong with the water if it killed the fish...You need to zero in on what that is, to figure out what killed your fish.
 
Flower,

So far, I have no problem, I used RO water, but I always not do what I suppose to do, here are what I did, I use 5 gallons buckle, add the salt into the RO water, put the powerhead in, have senility set up to 1.045, wait for 24 hours, put the heater in for three hours than split the water into two 5 gallons buckles, add more RO water in both buckles now the salinity is 1.025, put the water into DT.
 
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mandy111

Active Member
If tank is set up correctly, then ammonia and nitrites should NOT be in your system at all.
The most important thing with changes is matching the salinity and temp of existing water to be as close as possible.
The other parameters should be close too, but not quite as important to match as the other two mentioned above.
I don't think of my fish as in a bed, i think of them as in a toilet, the poop and wee in this water all the time, and although bacteria will consume most of it, water changes are and integral part of fish keeping.
If you killed your stock with a water change then you must have done something very wrong, If you haven't changed water for a long time and do a large change being it salt or freshwater, then yes you may have shocked your fish, with numbers dropping so suddenly
But I find it totally irresponsible to say "don't do water changes it kills fish ":
Any newbie out there needs to know that it does not kill fish if done properly and is a chore that needs to be done regularly.
Only a very very small amount of bacteria actually lives in the water column so even in an emergency situation you can do large 80-90% changes with no harm if parameters and temp are matched correctly.
 

flower

Well-Known Member
Flower,

So far, I have no problem, I used RO water, but I always not do what I suppose to do, here are what I did, I use 5 gallons buckle, add the salt into the RO water, put the powerhead in, have senility set up to 1.045, wait for 24 hours, put the heater in for three hours than split the water into two 5 gallons buckles, add more RO water in both buckles now the salinity is 1.025, put the water into DT.
Some containers leak certain chemicals, and are not good to ever use. If a bucket was ever used for anything besides fish, there could be residue from that (ask other family members if they use your fish buckets), since plastic absorbs and holds elements from what was ever put in it. If your container is open with no lid...stuff can fall into it, or if anything was sprayed around it...lots of things can go wrong. The water change in and of itself is not what kills the fish. There is something going on with the water you are using...either the water itself or the containers, but something bad is contaminating your change water if things go wrong right after that kills your fish.

Looking at your method... you should still wait before adding the water from the buckets once you split the original water and lowered the SG. It doesn't sound right that a 5g bucket of mixed saltwater registers 1.045 SG, and after split in half would register 1.025 right on the head. All you would need to drop 1.045 to 1.025 is maybe a gallon or two of water added to the original.
 

pegasus

Well-Known Member
When I first started in the saltwater hobby, water changes were the only thing that kept my fish alive. Although I had studied a lot, none of it really made sense until I had been at it for a while. My parameters were all over the place, and anything that could go wrong... did. I won't lie, I lost a quite a few fish by making mistakes along the way. I hate that I lost them, but I don't know of many in this hobby who hasn't murdered a few fish in the learning stages. It happens... but we learn from those mistakes. We figure out what went wrong, and we do everything we can to prevent it from happening again. Hard learned lessons are the ones you remember most. Once you get the hang of things, the death toll drops... or better yet... completely stops. Until you reach that point in the hobby, please don't give terrible advice like "water changes kill fish". That's completely and utterly preposterous... and as Mandy put it... totally irresponsible. Seasoned hobbyists will know better, but a newbie seeking advice might actually believe your "theory" and apply it to their practice. That would be a terrible mistake. To be completely honest, I find it strange Admin has allowed this post to stay active...
 

silverado61

Well-Known Member
I think he was just trying to insight a riot (so to speak). You notice he made his original comment and hasn't commented since. Like tossing a smoke bomb into a filled room then sits back and watches the chaos.
 

flower

Well-Known Member
I think he was just trying to insight a riot (so to speak). You notice he made his original comment and hasn't commented since. Like tossing a smoke bomb into a filled room then sits back and watches the chaos.
Lots of new members sign up, have their say and never return. At least he didn't ask a question and leave us hanging as most who do that do. It wasn't a total bust...this thread at least confirmed that water changes are needed, and why sometimes it can go wrong, and a few reasons why.
 

beaslbob

Well-Known Member
i have been into tropical fish forty years plus. do water changes hurt fish ? it depends. how much, how offten. lets say, your tank is cured, it has its own chemistry. when you water change, your adding mars to earth. your adding green salt water to cured salt water. to put it simple, like eating a raw carrot, to a cooked carrot. i do only a five percent water change every two, to three weeks. ammonia, is the main fish killer, nitrates, nitrites, are always there, no matter what you do. you can't do enough water changes to get rid of them. plus, you'll change your chemistry so much, your fish will stress out, and die. yes, water changes will kill fish, if done to much. remember, your fish lay in their bed, if you disturb their bed to much, they can't adjust, and will die. well, hope this helps people. i learned the hard way. $300.00 worth of fish. salt water. CHOW !
+1

see also

https://forums.saltwaterfish.com/index.php?threads/beaslbobs-water-change-analysis.369985/#post-3184504

Still just my .02
 

Bryce E

Active Member
The only real harm I've found by the amount of water changes I do is the harm to my pocket book due the the large amount of salt I go through. Lol.
 

bang guy

Moderator
It might just be me but I tend to avoid the advice of people who blame their tank crash on regular water changes.
 

bang guy

Moderator
How long you think add too many fish at once to be justify? After one week, all of my 9 new fish are doing great, everyone of them are happy with their new home.
I think that's great that all of your fish are currently doing well, I really do. An example of things working out despite going against advice.

Just because it worked once is not a good reason to start advising that it's good practice.

A few years ago a guy jumped off Niagara Falls and swam to shore unharmed. It worked for him just fine. Should he advise people that it's perfectly safe to jump off the falls?
 
Bang guy,

Add 9 Green Chromis / clowns are not the same add 9 tangs / big Angels, like I said it before, the total weight of my 9 new fish, should be less than two 3-inches of big fish, you cannot go by the number of fish.
 
Bang guy,

"Against Advice" = I do against your advice in regarding Clownfish, which I have a lot of experience from, I have added three more clowns, and now all three new members are following my B&W Clown every where, the two Maroons are still on the bottom left corner.
 
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