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

[JackBlasto]

So, I'm sure that title probably really perks some ears up... I'm wondering if you monitor and keep you nitrates/nitrites/phosphates in control what is the point of water changes? I can understand replacing fertilizers and trace minerals that the plants eat up and need more of but as far as my water being a potential threat to it's living inhabitants (8 fish) I'm wondering aloud that water changes are necessary? What would become harmful to the fish by not changing water given my nitrates are always below 15 ppm, phosphates below 2 ppm?

P.S. I'm not trying to sound like a jerk posting this. I really am curious.

 

[bshenanagins]

So, I'm sure that title probably really perks some ears up... I'm wondering if you monitor and keep you nitrates/nitrites/phosphates in control what is the point of water changes? I can understand replacing fertilizers and trace minerals that the plants eat up and need more of but as far as my water being a potential threat to it's living inhabitants (8 fish) I'm wondering aloud that water changes are necessary? What would become harmful to the fish by not changing water given my nitrates are always below 15 ppm, phosphates below 2 ppm?

P.S. I'm not trying to sound like a jerk posting this. I really am curious.

There are other metals that exist in our tap that will build up over time that really are not good for any living being. The only widely available tests we have for aquariums are for nitrogen, which are the most harmful and become toxic much more quickly. So nitrogenous wastes are not the only forms of waste that need to be physically removed. Whatever the BB misses, some think activated carbon removes the rest when in actuality this is false. There are all sorts of waste that vary in particle size, I which the carbon can only absorb a certain range leaving the rest free floating. Think about the odors and chemicals in the air in your house, anything in the air will eventually reach your tank.

 

[dwayne.aycock]

You are kidding right? What's the point of changing your underwear....they will only get dirty again? Dilution is the solution to pollution, and dilution can only happen with water changes.

 

[GodFan]

So, I'm sure that title probably really perks some ears up... I'm wondering if you monitor and keep you nitrates/nitrites/phosphates in control what is the point of water changes? I can understand replacing fertilizers and trace minerals that the plants eat up and need more of but as far as my water being a potential threat to it's living inhabitants (8 fish) I'm wondering aloud that water changes are necessary? What would become harmful to the fish by not changing water given my nitrates are always below 15 ppm, phosphates below 2 ppm?

P.S. I'm not trying to sound like a jerk posting this. I really am curious.

PWCs are not necessary in a setup like gou described except if you have sensative fish. I would still do a little eater changing every few monhs though. Plenty of people have maintained fish for years without water changes.
This is contreversial and will probably end up making somebody very angry and both of us will probably get some rude responses here but in all honesty it works. It is the basis of the walstad method in fact!
There is a guy on another forum who had a tank he only did PWCs on once every 3-4 months and he had red cherry shrimp breeding in it!

 

[bud29]

I think that with occasional top-offs you can get away with not having to actually do a water change for a while. But water still does need to be changed at some point, to replenish minerals, trace elements, etc. Not even nature is a closed system. Many people only use nitrate readings as a trigger point for water changes, however there are other factors at play as well.

 

[dwayne.aycock]

I would hate to be a fish in one of your tanks. I can't get over the fact that you are ignoring the things that build up in the water column over time, that are only removed through changing the water. I know there are fish that can tolerate such conditions, but is it right to do so? To me, the aquarium is a giant kidney. It functions very effectively, but even your kidneys need to be flushed every so often. For example in an exaggerated sense....try drinking Vodka every day, and nothing else. Vodka has water in it which your body needs, but a lot of other things that are toxic to your body as well. In no time at all, you would be full of toxins, bloated and sick. With no interventions (water change) you would soon die. Is this what you are suggesting? I keep Discus...a very sensitive fish, but at the same time, routing partial water changes equaling 100% per month, find them thriving. Water changes take about 30 minutes per week in my case...not a big deal to say the least. Is a 25% change once per week too much for you? Not hating....just puzzled.
D

 

[GodFan]

I would hate to be a fish in one of your tanks. I can't get over the fact that you are ignoring the things that build up in the water column over time, that are only removed through changing the water. I know there are fish that can tolerate such conditions, but is it right to do so? To me, the aquarium is a giant kidney. It functions very effectively, but even your kidneys need to be flushed every so often. For example in an exaggerated sense....try drinking Vodka every day, and nothing else. Vodka has water in it which your body needs, but a lot of other things that are toxic to your body as well. In no time at all, you would be full of toxins, bloated and sick. With no interventions (water change) you would soon die. Is this what you are suggesting? I keep Discus...a very sensitive fish, but at the same time, routing partial water changes equaling 100% per month, find them thriving. Water changes take about 30 minutes per week in my case...not a big deal to say the least. Is a 25% change once per week too much for you? Not hating....just puzzled.
D

This is the typical response that I totally expected. Instead of listening to facts people will stay closeminded stuck in the standard beliefs in the hobby despite the facts. And probably accuse us of animal cruelty or the like.
I will not engage in a pointless argument like this with somebody who will ignore everything I say. So if you really are interested in discussing this and possibly opening your mind then reread my post carefully and ask a relavent question that does not include an accusation.
Sorry to be harsh but Im tired of pointlessly arguing with people who have made up their mind to not listen to anyone who doesnt agree with them.

 

[Sillyfishies]

I would hate to be a fish in one of your tanks. I can't get over the fact that you are ignoring the things that build up in the water column over time, that are only removed through changing the water. I know there are fish that can tolerate such conditions, but is it right to do so? To me, the aquarium is a giant kidney. It functions very effectively, but even your kidneys need to be flushed every so often. For example in an exaggerated sense....try drinking Vodka every day, and nothing else. Vodka has water in it which your body needs, but a lot of other things that are toxic to your body as well. In no time at all, you would be full of toxins, bloated and sick. With no interventions (water change) you would soon die. Is this what you are suggesting? I keep Discus...a very sensitive fish, but at the same time, routing partial water changes equaling 100% per month, find them thriving. Water changes take about 30 minutes per week in my case...not a big deal to say the least. Is a 25% change once per week too much for you? Not hating....just puzzled.
D

Actually vodka is used to get rid of nitrates in saltwater... Lol!

Anyway, I don't understand why discus need such large constant water changes. Lets say your tank is planted enough to where your nitrates stay 0. Do you still have to do the constant 50%+ waterchanges?

 

[Billbug68]

Actually vodka is used to get rid of nitrates in saltwater... Lol!

Anyway, I don't understand why discus need such large constant water changes. Lets say your tank is planted enough to where your nitrates stay 0. Do you still have to do the constant 50%+ waterchanges?

I think this was jacks point, if your plants uptake dangers like nitrates, then what's the point? But like said before, it's necessary to replenish trace minerals, etc., not only for the plants, but the fish use them to be healthy as well. I know for a fact that jack is mixing his own water so would top offs be enough to replenish what the fish need to stay healthy for an extended period of time? I know a lot of salt tanks go years without water changes, I've just never heard of it positively discussed on the FW side. Seriously, thanks jack, this is a great topic to discuss and learn from.

 

[Sillyfishies]

I think this was jacks point, if your plants uptake dangers like nitrates, then what's the point? But like said before, it's necessary to replenish trace minerals, etc., not only for the plants, but the fish use them to be healthy as well. I know for a fact that jack is mixing his own water so would top offs be enough to replenish what the fish need to stay healthy for an extended period of time? I know a lot of salt tanks go years without water changes, I've just never heard of it positively discussed on the FW side. Seriously, thanks jack, this is a great topic to discuss and learn from.

I don't understand why discus need more water changes then other fish, though. Given that you have enough plants to keep toxins down.

 

[bud29]

I would hate to be a fish in one of your tanks. I can't get over the fact that you are ignoring the things that build up in the water column over time, that are only removed through changing the water. I know there are fish that can tolerate such conditions, but is it right to do so? To me, the aquarium is a giant kidney. It functions very effectively, but even your kidneys need to be flushed every so often. For example in an exaggerated sense....try drinking Vodka every day, and nothing else. Vodka has water in it which your body needs, but a lot of other things that are toxic to your body as well. In no time at all, you would be full of toxins, bloated and sick. With no interventions (water change) you would soon die. Is this what you are suggesting? I keep Discus...a very sensitive fish, but at the same time, routing partial water changes equaling 100% per month, find them thriving. Water changes take about 30 minutes per week in my case...not a big deal to say the least. Is a 25% change once per week too much for you? Not hating....just puzzled.
D

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. I'm not advocating a 100% no water change schedule - I do believe that water changes are necessary - however in many cases not at the rate some think. Discus are a whole other ball game in terms of water change schedules, so they're not a good example at all.

Actually vodka is used to get rid of nitrates in saltwater... Lol!

Anyway, I don't understand why discus need such large constant water changes. Lets say your tank is planted enough to where your nitrates stay 0. Do you still have to do the constant 50%+ waterchanges?

As stated previously, there are other factors besides nitrates to take into account when deciding on water change schedule. From what I've gathered talking to a few discus people, discus are used to very frequent rains in the wild - so, many people do up to 90% daily water changes to ensure good discus growth. 'Infrequent' water changes can cause some degree of stunting. Once again, discus are an extreme outlier in a water change schedule conversation, so they're not a good example.

 

[Billbug68]

I don't understand why discus need more water changes then other fish, though. Given that you have enough plants to keep toxins down.

I think namely, wild caught discus need more water changes, or if you're breeding. They're supposedly incredibly sensitive and suseptable to disease, I believe.

Edit: And when you're paying upwards of $50+ per fish, it's hard to take chances...

 

[Sillyfishies]

I've seen people keep oscars in a 10 gallons, with no waterchanges; or top offs for years. So I think with low stocking and high planting, and top offs it COULD be possible. Most likely you would just delay the need for waterchanges.

From my understanding there is going to be people who say, "NO! Fish need weekly 50% waterchanges!" And none of them will have personal experience with it. And then there's the people who have successful ran a tank with next to no waterchanges.

 

[GodFan]

I always wondered why discus needed crazy pwcs as well lol thats the only reason I would never have them!
I used to believe in 100% no water changes being ok. After more discussions I have been in about it though I have come to the conclusion that some are necessary. Most of us with live plants could have thriving fish on 1 pwc a month. In my experience longer can be succesfully done. It depends on the species housed and if you have anything in your water plants cant nutrilize (I know its spelled wrong but Im tired lol)

 

[dwayne.aycock]

Not arguing or meaning to be difficult...just not getting your logic. I took more than my share of physics and chemistry courses while in college. Acids, bases and solvents were standard discussions. Water is a solvent used to do a lot of things, and is a requirement for biological life. Other than carbon, water was necessary for life. additionally, water was the universal transport of biological life in its ability to remove toxins and supply nutrients. In your example, you negate the fact that certain toxins are not removed by plants or absorbed by carbon or even metabolized by bacteria. Where do these toxins go? They do not evaporate, and they do not have a half life like certain radioactive isotopes. Where do they go? In my case, Discus are sensitive to these compounds and prove to be better off with routine water changes, and water of a certain quality. The easiest remedy for their requirements is water changes. When the water is not changed, nitrite and nitrate levels build up to unacceptable levels resulting in fish distress and eventually death. I also know that I am NOT going to change any opinions here. In the end, we do what works best for us in out particular situation. I will keep doing what I am doing, it works WELL for me.
D

 

[GodFan]

Not arguing or meaning to be difficult...just not getting your logic. I took more than my share of physics and chemistry courses while in college. Acids, bases and solvents were standard discussions. Water is a solvent used to do a lot of things, and is a requirement for biological life. Other than carbon, water was necessary for life. additionally, water was the universal transport of biological life in its ability to remove toxins and supply nutrients. In your example, you negate the fact that certain toxins are not removed by plants or absorbed by carbon or even metabolized by bacteria. Where do these toxins go? They do not evaporate, and they do not have a half life like certain radioactive isotopes. Where do they go? In my case, Discus are sensitive to these compounds and prove to be better off with routine water changes, and water of a certain quality. The easiest remedy for their requirements is water changes. When the water is not changed, nitrite and nitrate levels build up to unacceptable levels resulting in fish distress and eventually death. I also know that I am NOT going to change any opinions here. In the end, we do what works best for us in out particular situation. I will keep doing what I am doing, it works WELL for me.
D

First off NitrItr should NEVER build up or you need to cycle your tank. Second off we have exempted discus and other sensative fish from theis repeatedly. Also in most cases those other unused toxins can be adequatly controlled by doing a water change every few months! Barring extreme circumstances we should all be able to do once a month pwcs on our planted tanks.

 

[bud29]

Not arguing or meaning to be difficult...just not getting your logic. I took more than my share of physics and chemistry courses while in college. Acids, bases and solvents were standard discussions. Water is a solvent used to do a lot of things, and is a requirement for biological life. Other than carbon, water was necessary for life. additionally, water was the universal transport of biological life in its ability to remove toxins and supply nutrients. In your example, you negate the fact that certain toxins are not removed by plants or absorbed by carbon or even metabolized by bacteria. Where do these toxins go? They do not evaporate, and they do not have a half life like certain radioactive isotopes. Where do they go? In my case, Discus are sensitive to these compounds and prove to be better off with routine water changes, and water of a certain quality. The easiest remedy for their requirements is water changes. When the water is not changed, nitrite and nitrate levels build up to unacceptable levels resulting in fish distress and eventually death. I also know that I am NOT going to change any opinions here. In the end, we do what works best for us in out particular situation. I will keep doing what I am doing, it works WELL for me.
D

Nitrite will not will not build up over time, given a healthy biofilter. As for nitrates, many 'self-sustaining' setups have lots of fast-growing plants. These fast-growing plants take in lots of nitrate, keeping levels safe. In a non-planted tank, obviously it is much easier to have nitrate buildup, as you have no plants to counteract it. Concerning other toxins, we will probably need specific types listed to have any meaningful discussion.

 

[Dallascowboys16]

I believe everyone has valid points but I also believe that water changes once every month or two can be done with ease in a planted tank. Also I believe that water changes at are done often are very beneficial and do contribute to the overall Heath of the tank. Also without water changes done often fish waste builds up in the tank and would eventually cause dirty water. I will say that often I have gotten away with water changes with intrevals of a month or two at a time when life has gotten busy with just top offs and my sensitive fish species have been fine. As of now I currently do frequent water changes every week but you can get away with every month or two if you have enough plants and aren't too heavily stocked. Thanks for bringing this topic up! I think we need to discuss it more often!

 

[dwayne.aycock]

Discus fish are NOT hard to keep...to the contrary, they are quite simple. There are a couple of gospels that should not be violated, but beyond that, they are simple fish. They are VERY personable and interact with my fully. They follow my movements around the room, and wag their tails like dogs when I approach the tank. I can hand feed them, and even hold them in my hand and pet them. They recognize me and my Wife, but shy away from strangers like the exterminator or the refrigerator repair man. All they really require is patience, high water quality (I use 50/50 RO and tap water) and a good filter. Don't overfeed, and quarantine and fish or plants before adding to the tank. Finally keep them around 84 degrees. They appreciate the planted tank with a dark substrate.

 

[Oscar98]

I've seen people keep oscars in a 10 gallons, with no waterchanges; or top offs for years. So I think with low stocking and high planting, and top offs it COULD be possible. Most likely you would just delay the need for waterchanges. From my understanding there is going to be people who say, "NO! Fish need weekly 50% waterchanges!" And none of them will have personal experience with it. And then there's the people who have successful ran a tank with next to no waterchanges.

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.