Why are water changes necesary ?

[Lepomis]

I don't do water changes very regularly. I don't think (zkt) you are going to find what you are looking for. I would assume you are looking for goo old fashioned data. Someone that has kept a long term records on their water quality. More importantly parameters besides the common ones. You want the proof of deadly compounds needing removal/reduction by these weekly water changes. I don't do water changes often at all. I basically do a water change when I need to top off the tank, usually every 6 weeks or so. I don't see any fluctuations in my readings. People change water so often because, well that is just what is done or if it aint' broke don't fix it concept. It is overall a good practice because it is easier just to avoid potential problems.

 

[zkt]

Its a closed life- support system. Agaiin I refeer to the space station as a analogy.

 

[talloulou]

I believe that if all the processes are in balance it isnt necessary. The corys, gourami, and redfin sharks in my tank are testament to it. The dying off of the other species may be due to killing rather than toxins.
The way to tell is to remove all the agressive fish and see if the passive ones continue to die or not.

What are the wastes that are not removed by plants and filtration ?
The minerals are present in the tap water too and its a one for one replacement situation .

I believe you are incorrect and your observations aren't very scientific since you have no "control" tank. To prove your theory....no water changes are necessary in a balanced tank.....you would need two balanced tanks. Then you would need to perform water changes on one and no water changes on the other. You have one tank with species "dying" off so I think your a very long way from having a "balanced" system.

 

[talloulou]

. People change water so often because, well that is just what is done or if it aint' broke don't fix it concept. It is overall a good practice because it is easier just to avoid potential problems.

Fish can live in tanks that aren't well maintained but generally they are less colorful, less active, & more prone to disease. That is why most people change water so often. Also "topping off" is not a water change. And most people who think their tanks are doing great really have tanks that are suffering from old tank syndrome and this is realized as soon as they try to add something new to the tank and it dies within a day.

 

[zkt]

Im trying to find out what constitutes such a system.
Lepomis, i dont do more than top the level off every few days. Not taking anything out - just replenishing, as you. The corys , sharks and gouramis are fine.
It seems that you do water changes because it works. Thats fine. What works - works. But that does not disprove the existance of another method that works too.

 

[talloulou]

Lepomis, i dont do more than top the level off every few. Not taking anything out - just replenishing, as you. The corys , sharks and gouramis are fine.

Fine obviously means different things to different people. I doubt any of your fish will live nearly as long or as happy as they could if you cared for them. Good luck to you and yours......your gonna need it!

 

[PsiPro]

Its a closed life- support system. Agaiin I refeer to the space station as a analogy.

Not the best analogy, as they bring everything up there and its not self sufficient.

 

[kimberly]

One problem with the space station analogy...no one has had to live on the space station permanently. The people are cycled on & off. Your fish are not.

 

[zkt]

I take exception the the idea that my tank isnt wall maintained because I dont change the water. I strive to maintain a good plant growth rate as well as nitrifying bacteria, and a population of scavengers. Water changes might be the lazy way out.
I think theyve pretty well proven that it can be sustained indeinitely. The record is bout 3 years I think.
I bring supplies to the tank too. Water, filter chamges. food.

From the documentaries that ive seen about the amazon river and its tributaries- it aint none too clean. But you may say that there is some mysyerious process at work that makes it all healthy and nice. I just wanna know what it is thats duplicated by water changes,

 

[kimberly]

More on the space station and waste products.
http://www.pbs.org/spacestation/station/living_sanitation.htm

The wastes are not left in the system, that plus the fact that people are being cycled through makes the space station not a closed system.

In an aquarium, the inhabitants stay the same (barring birth, death or an lfs purchase) and the wastes are not put into sealed bags or opened to vacuum.

 

[kimberly]

Ha PsiPro, jinx on our posts!

 

[zkt]

Human waste can be turned into fertilizer but its not practicle on the space station.
If there is something in fish waste that plants bacteria, snails, and protozoa cant deal with - what is it?

 

[PsiPro]

I take exception the the idea that my tank isnt wall maintained because I dont change the water. I strive to maintain a good plant growth rate as well as nitrifying bacteria, and a population of scavengers. Water changes might be the lazy way out.
I think theyve pretty well proven that it can be sustained indeinitely. The record is bout 3 years I think.
I bring supplies to the tank too. Water, filter chamges. food.

From the documentaries that ive seen about the amazon river and its tributaries- it aint none too clean. But you may say that there is some mysyerious process at work that makes it all healthy and nice. I just wanna know what it is thats duplicated by water changes,

You do bring alot of stuff to the aquarium... but whens the last time you took stuff off? You know everything is toxic to some degree, it just depends on how much of it there is. You can die from drinking too much water (not drowning). If you keep adding stuff (food for example) to your aquarium and not taking anything out, the levels of it will eventually become toxic. The only way to have a completly self sufficient tank is to have somthing that converts the most basic waste into food for your fish, and becasue you do not have a complete ecosystem, and its difficult if not impossible to maintain, the waste will build up.

Many fish will adapt to it in time, but it will eventually become toxic.

 

[Lepomis]

I should have clarified that I do a water change when my water needs topping off. So I do more water changes in the winter (electric base board heating) and much fewer in the spring and summer. I do believe however most people change water because that is what they have been told (not because they recognize trouble signs).

 

[zkt]

plants+light+co2+O2 +nitrates+ phoshpates+ potassium compounds+ a little trace elements+ water=carbohydrates+ o2.
Yea , there might be some old wives tales at work here or wisdom of the ages maybe better said.

 

[PsiPro]

plants+light+co2+O2 +nitrates+ phoshpates+ potassium compounds+ a little trace elements+ water=carbohydrates+ o2.

Thats correct now those carbohydrates are stored in the plant, do your fish eat plants?

 

[zkt]

They are stored as plant matter. Which, as it increases, further lowers the amount of fish wastes in the water. SOme do. I trim them too.
Im not saying that water changes arent necessary. Just that in a properly set up tank they arent. And if they are always necessary - why?

 

[PsiPro]

In theory its good, I'm trying my self for a self sufficent tank, but i'm still changing water. By all means try it, I'm sure you will get plenty of support here if you post your levels of everything and document the lifespan of your animals.

Your tank will survive without water changes. I have three tanks I have never done water changes in, but the tanks that I do water changes in are by far more healthy.

 

[malkore]

zkt, it pretty much appears you're just looking for an arguement, and that nothing short of a member with a Ph D in aquatic Biology is going to convince you differently.

Well here are my comments: fish waste breaks down into more than nitrate and phosphate..you end up with countless other DOC's in the water. If you don't remove them, fish's health will suffer. In your pond, you apparently let water evaporate, and fill it up with new water...thus increasing hardness levels in the pond since calcium carbonate cannot evaporate.

Here's my analogy: have you even been to a tiny, man made lake, that wasn't part of a large canal system? basically the lake doesn't have a constantly renewing water source and the old water doesn't flow out of the lake. The lake will smell fishy...it won't seem anywhere near as clean or clear as a lake that DOES have an inlet and outlet and always circulating new water in.


In conclusion, if you plan to continue advocating 'no water changes' around here, you better have about 20 scientific articles with all your citations ready, so you can defend your position. Otherwise, you appear to be nothing more than a troll.

 

[Hara]

I am thinking that zkt sounds alot like another member we used to have here....is this you zac? Zac loved to argue for the sake of argument and this is looking seriously familiar.