What's the point of water changes, really!?

[bud29]

Thats easily an exaggeration. My tanks lose around 5g of water from the 55s and 10g from the 150 just because of it evaporating. You can not keep an oscar in a 10g tank with no water changes or top offs longer than 8months without it dying. And even 8 months would be h one earth for said oscar.

It may very well be an exaggeration, but I don't think the example was important as the point trying to be made - people have gone extremely long times without a water change, so a once-a-month pwc schedule can be fine in many cases.

 

[Oscar98]

It may very well be an exaggeration, but I don't think the example was important as the point trying to be made - people have gone wayyy longer without a water change than 1 month, so in many cases, a 'relaxed' pwc schedule can be perfectly fine.

I agree, i missed two weeks of water changes on my 150g because in the last two weeks ive had 7 soccer games and 6 big tests and hours of homework. But its a big tank and all the fish are smaller than 5" than are in it. And the params were fine. But i still felt bad for not doing them so i did a wc on sat and monday. Im pretty religious with them since all my fish are juvies and i wNt them to grow as fast and healthy as possible

 

[aqua_chem]

How confident are you that nitrogenous waste, phosphates, and GH/KH are the only thing that builds up? Don't make the mistake of confusing undetectable/unmeasureable with not there.


Fish don't just excrete ammonia. They excrete many, many organic molecules (metabolites, proteins, etc) that could potentially be toxic. These compounds could have a number of potentially hazardous effects on a tank, such as (and completely made up on the spot): noxious to fish gills, bioaccumulation, or fueling dangerous (or unsightly) heterotrophic bacteria or algae species like cyanobacteria.


Will your fish be ok? How tough are your fish? How tough do you think they have to be to live? In the end of the day, it might just be a quality of life issue rather than life-or-death, but if so, being too lazy to do adequate water changes is not an excuse for anything. If you can't fulfill the requirements of owning a pet, then you should probably examine your reasoning for having it.

 

[GodFan]

How confident are you that nitrogenous waste, phosphates, and GH/KH are the only thing that builds up? Don't make the mistake of confusing undetectable/unmeasureable with not there.

Fish don't just excrete ammonia. They excrete many, many organic molecules (metabolites, proteins, etc) that could potentially be toxic. These compounds could have a number of potentially hazardous effects on a tank, such as (and completely made up on the spot): noxious to fish gills, bioaccumulation, or fueling dangerous (or unsightly) heterotrophic bacteria or algae species like cyanobacteria.

Will your fish be ok? How tough are your fish? How tough do you think they have to be to live? In the end of the day, it might just be a quality of life issue rather than life-or-death, but if so, being too lazy to do adequate water changes is not an excuse for anything. If you can't fulfill the requirements of owning a pet, then you should probably examine your reasoning for having it.

Ok once again go back and read the conversation BEFORE you stick your foot in your mouth. SEVERAL people have posted saying that we reconize other materials may build up. We have acknowledged that fact. We have also stated that while no water changes may not be safe less frequent certainly be fine. I have shrimp breeding in water that geys changed once every month or 2. Another person breed them prolifically in water changed once every 3-4 months.
So yes PWCs are necessary but not nearly as much as people commonly think.
And on the lazy comment. My Dad had a saying growing up. "Work smarter not harder". You do your weekly water changes. I am content and my fish equally happy with once a month.

 

[Billbug68]

How confident are you that nitrogenous waste, phosphates, and GH/KH are the only thing that builds up? Don't make the mistake of confusing undetectable/unmeasureable with not there.

Fish don't just excrete ammonia. They excrete many, many organic molecules (metabolites, proteins, etc) that could potentially be toxic. These compounds could have a number of potentially hazardous effects on a tank, such as (and completely made up on the spot): noxious to fish gills, bioaccumulation, or fueling dangerous (or unsightly) heterotrophic bacteria or algae species like cyanobacteria.

Will your fish be ok? How tough are your fish? How tough do you think they have to be to live? In the end of the day, it might just be a quality of life issue rather than life-or-death, but if so, being too lazy to do adequate water changes is not an excuse for anything. If you can't fulfill the requirements of owning a pet, then you should probably examine your reasoning for having it.

I don't believe the point of the debate was about being too lazy to do water changes. It's WHY they are necessary if the plants uptake the toxins we test for. So specifically, what else is in the water that doesn't get removed by fish or plants? What doesn't get replaced by top offs to give fish what they need?

 

[Sillyfishies]

I'm used to do 50%+ weekly waterchanges. I later found out my tap has .50 ppm of ammonia. Now I don't do as big of water changes because I know I'm just introducing more toxins. So currently it's beneficial to not do big constant water changes because my plants keep nitrates down.

 

[aqua_chem]

Yikes! I was just offering my perspective on the matter, and in doing so agreeing with sentiment already expressed in the 24h-ish this conversation has been going. This is a fallacy that is endemic in the hobby, ie, putting stock into things we can measure that might not matter that much (GH, pH, etc) and forgetting things that are difficult to measure (TDS, NOM, etc), so I felt inclined to add something even if it had already been stated, if for no other reason than for emphasis.


I mention the last bit for two reason. One, because short of a purely academic question, that's the main reason people try to get out of water changes. And two, remember that these conversations are stored long term on the internet and could be found by someone just starting out that doesn't know better. It's a statement that should be included every time this is brought up even if it's implicitly understood.

 

[aqua_chem]

I'm used to do 50%+ weekly waterchanges. I later found out my tap has .50 ppm of ammonia. Now I don't do as big of water changes because I know I'm just introducing more toxins. So currently it's beneficial to not do big constant water changes because my plants keep nitrates down.

If you're on city water, a lot of that is probably chloramines that are detoxified by Prime (or most other water conditioners). A good biofilter would chew through that in a matter of hours.

 

[Sillyfishies]

If you're on city water, a lot of that is probably chloramines that are detoxified by Prime (or most other water conditioners). A good biofilter would chew through that in a matter of hours.

After doing a 50% water change, the next day ammonia was at .25... Not sure.

On the bright side, i found out that a local aquarium company gives out FREE RO water. They say you can bring a tub and get as much as you want...

It is possible to keep a saltwater fish-only tank without waterchanges, correct?

 

[aqua_chem]

After doing a 50% water change, the next day ammonia was at .25... Not sure.

Even if it were ammonia, a biofilter would go through that much ammonia overnight. 50% water change with .50 ppm ammonia = .25 ppm ammonia in the tank afterwards. When cycling a tank, some people consider the tank cycled when it can go through 4 ppm of ammonia in 24 hours. The amounts you're dealing with should be chump change.

As to your other question, I think it would be better addressed in a different subforum.

 

[jordanlee123]

If you fish normal environment is a puddle pond with out free flowing water they still get fresh water from rain I would say every where a fish is the water is changed alot I would like to say all people have to do is a small water change a week why would you want to risk the fish you love and played for

 

[GodFan]

Again I really think that we are over estimating the toxins that are immeasurable. They are low in concentration. If once a month PWC can keep them under control and the fish are just as happy and healthy then why not?

 

[azmodan]

Again I really think that we are over estimating the toxins that are immeasurable. They are low in concentration. If once a month PWC can keep them under control and the fish are just as happy and healthy then why not?

Just out of curiosity how exactly do you measure how happy and healthy your fish are?

 

[GodFan]

Just out of curiosity how exactly do you measure how happy and healthy your fish are?

Watch for signs of stress first off. My red cherry shrimp are breeding which they woukdnt do in adverse conditions. It isnt that hard to do. We all do it.

 

[Cactuspixie]

http://www.seachem.com/Library/Articles/Basics_of_Aquarium_Filtration.pdf

This article explains it quite well (for me anyway)

 

[Cactuspixie]

Also, topoffs will reduce TDS as well.

This statement is untrue. The only thing being evaporated is the water, so anything that is dissolved in the water becomes more concentrated. You can top the water back up, but the original amount of TDS is still there, and will keep increasing, despite regular top offs.
The only way to reduce TDS is to physically remove them from the system via water changes.

 

[Billbug68]

This statement is untrue. The only thing being evaporated is the water, so anything that is dissolved in the water becomes more concentrated. You can top the water back up, but the original amount of TDS is still there, and will keep increasing, despite regular top offs.
The only way to reduce TDS is to physically remove them from the system via water changes.

If you're doing water changes with tap, then you're just adding dissolved solids back in. If you're topping off with tap, you'll increase TDS, if you top off with RO or distilled water, then you won't be adding any extra dissolved solids, in theory keeping TDS stable. Now whether or not plants or fish uptake dissolved solids is the real question, then top offs with RO or distilled WOULD decrease TDS. I think I need, or we all need to read Diana Walstad's book... I may do an experiment with this topic...

 

[Cactuspixie]

If you're doing water changes with tap, then you're just adding dissolved solids back in. If you're topping off with tap, you'll increase TDS, if you top off with RO or distilled water, then you won't be adding any extra dissolved solids, in theory keeping TDS stable. Now whether or not plants or fish uptake dissolved solids is the real question, then top offs with RO or distilled WOULD decrease TDS. I think I need, or we all need to read Diana Walstad's book... I may do an experiment with this topic...

It's not about adding TDS in the top up water- the life within the tank is producing them- plants, fish, inverts etc.

 

[bud29]

This statement is untrue. The only thing being evaporated is the water, so anything that is dissolved in the water becomes more concentrated. You can top the water back up, but the original amount of TDS is still there, and will keep increasing, despite regular top offs.
The only way to reduce TDS is to physically remove them from the system via water changes.

Perhaps I phrased that incorrectly - topoffs will reduce the concentration of TDS. The effect is more prominent when you use RO water, but it still works with tap water (granted the water you put in has a lower TDS than the tank water, which it should). I am well aware that doing topoffs will not take dissolved solids out of the water.

 

[BillD]

I'd hate to be a fish in ANY tank

TDS does build up over time - yes. However, many species can healthfully tolerate a wide range. Also, topoffs will reduce TDS as well.


This is, in fact, not true. Top offs will increase TDS over time, particularly if using tap water. While most fish can tolerate a large range of TDs, sudden change, such as when water is changed, can kill fish, through osmotic shock.
Osmotic shock is more than likely the true culprit behind the myth of pH shock.
Regardless, you can't change too much water. Water from a relatively stable single source will keep tank parameters relatively stable if changed on a regular basis, before the parameters in the tank change from those of the source water.
Much is made up of what the test kits tell us, but of of the other chemicals, metabolic wastes, and pathogens. If you remove 50% of the water, as an example, you also remove 50% of dissolved metabolic waste, unknown chemicals, and pathogens. Raise a batch of angel fry without doing large regular water changes, and it will demonstrate all you need to know about water changes and their effects.