Are Water Changes Actually Necessary?

[kazvorpal]

The point is that over time there will be a build of a "things" (whether that be nutrients, or hormones, or whatever) that the filtration in a conventional tank cannot take care of. As many have mentioned, the point of doing water changes is to maintain a relatively balanced level of "water quality" (and I use that term loosely). By replacing portions of the tank water on a regular basis with water that is filtered beyond the capabilities of an aquarium filtration system, that balance is being maintained.

Hormones are a good argument...but it seems very unlikely that they accumulate long-term. They are volatile organic compounds.

Also, (and I apologize for the logical fallacy but I feel the point needs to be reiterated) if IACUC, the organization in the US that is charged with the responsibility of maintaining the health of laboratory animals, requires water changes in labs using fish, I have to believe that they are a "necessary evil," as you labeled them. If IACUC did not deem them necessary, they wouldn't require it, simple as that. IACUC makes the lives of researchers hard enough, and I can only imagine the time/expense that large fish labs must put into water changes (I work in a rodent lab so I see first hand how their rules affect our operating procedures). If it wasn't necessary for the safety of the animals they'd have a pile of angry scientists coming after them.

So back when the IACUC said that we must all use under-gravel filters, then you had to assume that everyone SHOULD use them, even though they appear to have been a really, really bad idea. And in the 1950s/60s, when the medical establishment said that breast feeding was something to be avoided, then everyone should have obeyed them.

Trusting the rules of a bureaucracy is one of the worst kinds of authority-worship.

Actually, I'm not certain the IACUC does not STILL say that under-gravel filters are required. I would assume they just say "adequate filtration". But at one time, only UGF was considered adequate.

What do their guidelines say about freshwater deep sand beds?

 

[Star_Rider]

ahh phosphates.. if the algae grow and use phosphates then algae may eventually be problematic, since we keep adding phosphates thru feeding perpetuating the imbalance. which requiring more maintenance to keep the tank clean and the fish visible..
which would sort of defeat the purpose of having a fish tank.

(one possible outcome)

 

[kazvorpal]

ahh phosphates.. if the algae grow and use phosphates then algae may eventually be problematic, since we keep adding phosphates thru feeding perpetuating the imbalance. which requiring more maintenance to keep the tank clean and the fish visible..
which would sort of defeat the purpose of having a fish tank.

(one possible outcome)

That's why you use macro algae, or fast-growing freshwater plants, and "harvest" them periodically. When you do, you remove the phosphates.

 

[Star_Rider]

or do water changes to remove the phosphates thereby reducing the phosphates which reduces the algae.
GSA is a PIA in an acrylic tank BTW

water changes are simpler to perform...and my plants in the garden seem to benefit from the water.

 

[DGalt]

Kav you complain of flawed arguments and yet what valid argument are you making?

Your assumptions seem to be
1. New filtration technology can take care of the nitrate cycle
2. A fish who has adapted to the conditions of the tank can live in said tank

There are a multitude of variables that you are not accounting for, the largest of which is the condition of living of the fish.

The average aquarist does not have the tools available to precisely measure and modify the water conditions of his/her tank so that they are optimal for the fish. A weekly (or bi-weekly or whatever) water change is the simplest way for the average person to keep the water in relatively good condition.

It's the same philosophy that goes into the EI dosing method that so many of us use in our planted tanks. We don't have the ability to measure every little nutrient in the water, so we go by general rules that have been shown to work. Each week we add an excess of nutrients and then hit the restart button at the end of the week. This allows for the maintenance of stable conditions.

Let us be serious here. We are taking animals out of their natural environment, which they have evolved/adapted to over tens/hundreds/thousands/etc. of centuries and putting them in a glass box of water and telling them "ok now adapt to this." I'd much rather have them stressed for 1 hr a week then have to constantly be adapting to slight changes in water conditions over the course of their lifetime

 

[kazvorpal]

Kav you complain of flawed arguments and yet what valid argument are you making?

Your assumptions seem to be
1. New filtration technology can take care of the nitrate cycle
2. A fish who has adapted to the conditions of the tank can live in said tank

1. I am citing nature's filtration technology, really. A deep sand bed, ceramic foam, mud filter, et cetera all come closer to simulating the way the world maintains its bodies of water.

2. That is a truism. If the fish are living in the tank, they are living in the tank. The guy citing old tank syndrome effectively admits that those fish are living in that water.

The average aquarist does not have the tools available to precisely measure and modify the water conditions of his/her tank so that they are optimal for the fish. A weekly (or bi-weekly or whatever) water change is the simplest way for the average person to keep the water in relatively good condition.

Actually, that just makes water-changes a lazy fix. Expecting them to test could easily be seen as another necessary cost, like expecting them to have filtration.

On the other hand, "I do routine changes because I don't feel like testing" is reasonable...just not a reason for changes to be seen as "necessary".

It's the same philosophy that goes into the EI dosing method that so many of us use in our planted tanks. We don't have the ability to measure every little nutrient in the water, so we go by general rules that have been shown to work. Each week we add an excess of nutrients and then hit the restart button at the end of the week. This allows for the maintenance of stable conditions.

I agree, because I'm too lazy to test the water for my plants. But, really, we can overdose because of this, and sometimes that is the cause of mysterious problems we have. It just mostly works out, much of the time, for many of us, which is sufficient.

Let us be serious here. We are taking animals out of their natural environment, which they have evolved/adapted to over tens/hundreds/thousands/etc. of centuries and putting them in a glass box of water and telling them "ok now adapt to this." I'd much rather have them stressed for 1 hr a week then have to constantly be adapting to slight changes in water conditions over the course of their lifetime

Let's be realistic here:

We want the tanks clean and pretty, which is a radical and needless departure from their natural environment that we could avoid. THAT is part of why many people over-clean their tanks, why they avoided deep sand beds for years, why they preferred under-gravel filters (that suck all unpretty stuff down where it's unseen, to rot on us later), why too many of us struggle to keep healthy algae out of our tanks (where nature expects it to be), et cetera.

I am actually arguing, in part, for an approach that is more natural, which is another solution to the problem you reasonably describe above.

 

[mx4ever]

Agree with above post. Also, someone once gave me this very basic analogy, but true nonetheless: "Imagine somebody put you in a sealed room and you were forced to breath the same air for weeks on end. Wouldn't you, at some point, be glad that they opened a window?" It's the same principle for fish. And I highly doubt that you are really stressing your fish THAT MUCH with weekly water changes providing your temperature matching the water, using adequate dechlorinator, and not causing a tsunami when you put water into the tank. Come on people, If your that lazy, just buy a python. Plus hauling five gallon buckets is zen-like work lol.

 

[Ozymandias]

now i do water changes say every week about 25%-50%, the whole reson i do this is because i have a planted tank. now it's a high light tank and i do ad fertilizers daily so i try to balance that amount of minerals and such in my tank. esentally i have some compondes be eaten up by my plant reall fast while other ones accumulate. so in esence when i do water chages in my tanks i'm removing those compounds but also adding other ones that when i do water changes. i do this with low light tanks too (even if it's on it a difrent time scale).

i also would ague a little stress ins't harm full in the long run and might be beneficial. i mean some people think the human body needs some level of cyanide even though in large does it will kill. i also be believe there have been some studies that say stress can be beneficial in human and other animals (don't quote me there tho) the varry fact also that fish have adapted to as you say to spawn or gain color when thay are stressed during the rainy season might say something about the necessity to do water changes in general. i mean the spawning might actually be vary beneficial to them in the long run.

 

[blue2fyre]

What about tanks that are overstocked and have no plants?

I would think those would need water changes.

 

[Fishfriend1]

I think a water change should be done at least every 2 weeks. I do a 30% water change every week. You your self would not want to be swimming in your waste water or would you? My fish are no different than my dog.
They all have feelings. There part of the family. They all depend on us to take care of them. :mwave:

:dance::dance::dance::dance::dance::worthy:
LOVED THAT IDEA!