Water changes

[AlexT]

I've found that plants have a lot to do with lowering nitrates over time.

I have one tank that doesn't have as many plants as others ones I keep. It has sand only substrate and doesn't keep plants very well. It is a 10 gallon tank. The 5 green emerlad corydoras don't help with keeping the plants either. The tank also has 3 zebra danio. All of these fish are around a year old now and I've never had any issues with them. The nitrates can get to around 80ppm. I've started doing more water changes and it stays at around 20ppm by me doing that. I give about 4 sinking Omega One catfish pellets for the corys and a fairly mall pinch of flakes for the danios once per day. There's also 2 assasin snails in there so they eat as well. Am I overfeeding?

I do have some plants in the 10 gallon tank. One of them being a lilly which is taking up almost half side of the tank now. The corys love it under the pads. There's a few other plants growing too now. It's just slow going.

Same, I know there is a strong case that plants take up ammonia as the preference and apparently it's not so easy or normal for plants to take up ammonia and then take up the nitrate. I was reading on here. Maybe from Byron. All I know is that in every set up I've had with plants, the nitrate in the tank gets below the source Nitrate (tap) because in London, UK it's normal for tap water to be around the 15-20ppm and, actually, when I was in the hobby before, about 10yrs back, I was getting 40ppm Nitrate in the tap. The legal max is 50ppm. And my planted tanks have always been heavily stocked as well with fish. I've been able to have 40ppm in the tap water at water change, and 10ppm in the actual tank water, sometimes 5ppm.

 

[Byron]

I've found that plants have a lot to do with lowering nitrates over time.

I have one tank that doesn't have as many plants as others ones I keep. It has sand only substrate and doesn't keep plants very well. It is a 10 gallon tank. The 5 green emerlad corydoras don't help with keeping the plants either. The tank also has 3 zebra danio. All of these fish are around a year old now and I've never had any issues with them. The nitrates can get to around 80ppm. I've started doing more water changes and it stays at around 20ppm by me doing that. I give about 4 sinking Omega One catfish pellets for the corys and a fairly mall pinch of flakes for the danios once per day. There's also 2 assasin snails in there so they eat as well. Am I overfeeding?

I do have some plants in the 10 gallon tank. One of them being a lilly which is taking up almost half side of the tank now. The corys love it under the pads. There's a few other plants growing too now. It's just slow going.

Something is way off here, let's see if we can figure it out. First, do you have nitrate in the tap water on its own?

The reason nitrate is low (or should be) in aquatic plant tanks is because the plants prefer ammonia/ammonium, and they literally grab all they can. And they are faster at this than the nitrifying bacteria. That means very little ammonia/ammonium gets taken up by the nitrifiers, which in turn means lower nitrite and then lower nitrate, since the plant's use of ammonia/ammonium does not produce nitrite or nitrate. Second, theytwill not turn to nitrate unless forced, because it takes the plant about 24 hours to "change gears," and when they do, they then have to expend considerable energy converting the nitrate back into ammonium. So it is a "last resort"measure. There is also, according to a study cited in Walstad, evidence that plants would prefer nitrite over nitrate, but for the same reasons they do not do this unless they have no other options. Most of us with low-tech or natural planted tanks will never see plants turning to nitrite/nitrate because the ammonia is so plentiful it is hardly going to run out without other nutrients (carbon especially) and light not being adequate anyway.

Nitrate is poisonous to fish, as is ammonia and nitrite, but it acts differently. I had a good discussion with Neale Monks about this, and he said the thinking now is that nitrate slowly weakens the fish, making it more susceptible to other things such as disease. And stress, which is behind 90% of all aquarium fish disease. Levels vary depending upon the fish species and the exposure time, but he advises that it should never be allowed to rise above 20 ppm, and there are species that will have serious issues with even this--cichlids are known to be highly sensitive to nitrate, and on the cichlid sites they are now advising that diseases like hole-in-the-head is more likely nitrate-related than previously thought. Malawi bloat has also been linked to nitrate.

If you wish, we can look at issues causing this and suggest possible corrective measure, once we know the tap water question.

 

[AlexT]

Something is way off here, let's see if we can figure it out. First, do you have nitrate in the tap water on its own?

The reason nitrate is low (or should be) in aquatic plant tanks is because the plants prefer ammonia/ammonium, and they literally grab all they can. And they are faster at this than the nitrifying bacteria. That means very little ammonia/ammonium gets taken up by the nitrifiers, which in turn means lower nitrite and then lower nitrate, since the plant's use of ammonia/ammonium does not produce nitrite or nitrate. Second, theytwill not turn to nitrate unless forced, because it takes the plant about 24 hours to "change gears," and when they do, they then have to expend considerable energy converting the nitrate back into ammonium. So it is a "last resort"measure. There is also, according to a study cited in Walstad, evidence that plants would prefer nitrite over nitrate, but for the same reasons they do not do this unless they have no other options. Most of us with low-tech or natural planted tanks will never see plants turning to nitrite/nitrate because the ammonia is so plentiful it is hardly going to run out without other nutrients (carbon especially) and light not being adequate anyway.

Nitrate is poisonous to fish, as is ammonia and nitrite, but it acts differently. I had a good discussion with Neale Monks about this, and he said the thinking now is that nitrate slowly weakens the fish, making it more susceptible to other things such as disease. And stress, which is behind 90% of all aquarium fish disease. Levels vary depending upon the fish species and the exposure time, but he advises that it should never be allowed to rise above 20 ppm, and there are species that will have serious issues with even this--cichlids are known to be highly sensitive to nitrate, and on the cichlid sites they are now advising that diseases like hole-in-the-head is more likely nitrate-related than previously thought. Malawi bloat has also been linked to nitrate.

If you wish, we can look at issues causing this and suggest possible corrective measure, once we know the tap water question.

I posted above Byron. Back then about 10yrs ago, tap nitrate for me was about 40ppm. I remember this clearly. The UK max is 50ppm.

I had a 550 litre tank with Red Parrots (large ones, and a big group), Birchir's, Reed fish and a pink tailed chalceus. I had a 300 litre with a mix of Malawi and I had a 300 litre that was heavily planted community and heavily stocked (photo below).

I had to constantly do large water changes to keep the 550 litre and Malawi tank to even under 50 or so ppm Nitrate, whilst in my planted 300 litre, I was constantly getting 10ppm and even 5ppm nitrate. I was still doing regular water changes in the planted tank. I guess an average of about 30-40% every 10 days or so. The other tanks were every week. I tested all the time, I was, and am still, a testing freak. So, with 40ppm tap water going in regular, I was still getting 10ppm nitrate. I don't ever remember a reading of over 20ppm that's for sure, in my planted tank.

 

[Ram419]

Something is way off here, let's see if we can figure it out. First, do you have nitrate in the tap water on its own?

The reason nitrate is low (or should be) in aquatic plant tanks is because the plants prefer ammonia/ammonium, and they literally grab all they can. And they are faster at this than the nitrifying bacteria. That means very little ammonia/ammonium gets taken up by the nitrifiers, which in turn means lower nitrite and then lower nitrate, since the plant's use of ammonia/ammonium does not produce nitrite or nitrate. Second, theytwill not turn to nitrate unless forced, because it takes the plant about 24 hours to "change gears," and when they do, they then have to expend considerable energy converting the nitrate back into ammonium. So it is a "last resort"measure. There is also, according to a study cited in Walstad, evidence that plants would prefer nitrite over nitrate, but for the same reasons they do not do this unless they have no other options. Most of us with low-tech or natural planted tanks will never see plants turning to nitrite/nitrate because the ammonia is so plentiful it is hardly going to run out without other nutrients (carbon especially) and light not being adequate anyway.

Nitrate is poisonous to fish, as is ammonia and nitrite, but it acts differently. I had a good discussion with Neale Monks about this, and he said the thinking now is that nitrate slowly weakens the fish, making it more susceptible to other things such as disease. And stress, which is behind 90% of all aquarium fish disease. Levels vary depending upon the fish species and the exposure time, but he advises that it should never be allowed to rise above 20 ppm, and there are species that will have serious issues with even this--cichlids are known to be highly sensitive to nitrate, and on the cichlid sites they are now advising that diseases like hole-in-the-head is more likely nitrate-related than previously thought. Malawi bloat has also been linked to nitrate.

If you wish, we can look at issues causing this and suggest possible corrective measure, once we know the tap water question.

See the issue is, I have 5 other freshwater tanks of varying sizes (One 3 gallon, Two 5 gallons, One 10 gallon, One 20 gallon, One 55 gallon). All use the same tap water. So if the source water is the issue then how is it that the other tanks do not have the same issue?

I have just tested my source water for nitrates and wouldn't you know, there's nitrates in it! About 10ppm nitrates to be exact. Does that mean the other tanks are able to absorb the nitrates from the source water quicker?
One of my 5 gallon tanks constanly reads 0 nitrates. It only has 2 young guppy in it and some snails though.

 

[10 Tanks]

If I am correctly understanding this, I do not agree with a couple points. First, it is certainly possible to have stable water parameters and conditions. That is the point of water changes. Various forms of "pollution" increase and the only way to remove them is a water change. If the tank is overstocked, remove some fish. If it is overfed, stop. These are not justifiable excuses for poor maintenance. The fact is that the more water changed regularly, the better for the fish. If we cannot have a flow-through, agreed, then we up the volume of the water changes.

Changing for example 70% once a week removes 70% of the pollutants once a week. Removing 10% every day comes no where near this, as each day you are leaving behind 90% and it accumulates and accumulates.

Byron. I couldn't agree more! The tank hobby is 100 percent about keeping the water clear of dissolving waste material. The large, very frequent water change is the single, most important thing you can do to keep whatever living thing you have in the tank healthy.

10 Tanks (Now 11)

 

[Aqua67]

How often do people do water changes?
How much do people change?
Ive seen everything from 10% 25% 50%.
I have several tanks and all are fine however I've just got my daughter a small 40l tank with guppies in and at first everything was fine they were breeding and the fry were thriving.
5 months later guppies are dying weekly and I don't know what the problem is.
I do weekly water changes of 10% is that too much? Too little?

Just throwing in my two cents…. I change water about once a month, roughly 25% in most of my tanks which are lightly populated (70%) and heavily planted. I feed the inhabitants lightly every other day. The only deaths I’ve had recently was a 3 day power outage in the winter before we got our generator to provide life support to our aquariums and our refrigerator/well pump.

One of the tanks I’m referring to is an open top aquarium that that tank takes 3 gallons of new RO water weekly. I never see nitrates over 10ppm in that tank. (30 gallon - 1 angel, 1 SAE, 3 Kuhli loaches, 5 neons) Yes, lower than recommended loaches/neons to winter power outage deaths. Water got very cold.

The larger tank has a lid and doesn’t have as much evaporation. 38 gallons - 3 cories, 1 SAE, 4 glass cats and 17 ember tetras. This tank usually needs more water changes than the other two tanks.

Your guppy problem could have several factors. They’re often overbred and inbred so genetics can play a role, weakened stock. If they are multiplying quickly it could have something to do with the water or other substances getting into the water (freshly soap-washed hands, lotions, cleaning sprays used nearby, etc…). Perhaps one became sick and now it is working its way through the school on the weaker guppies.

Good luck with the tank and I hope your daughter enjoys the wonderful hobby of fish keeping.

 

[Byron]

See the issue is, I have 5 other freshwater tanks of varying sizes (One 3 gallon, Two 5 gallons, One 10 gallon, One 20 gallon, One 55 gallon). All use the same tap water. So if the source water is the issue then how is it that the other tanks do not have the same issue?

I have just tested my source water for nitrates and wouldn't you know, there's nitrates in it! About 10ppm nitrates to be exact. Does that mean the other tanks are able to absorb the nitrates from the source water quicker?
One of my 5 gallon tanks constanly reads 0 nitrates. It only has 2 young guppy in it and some snails though.

View attachment 327542

It is worth knowing what is actually coming in with your water. But 10ppm is a far cry from 80ppm which is a risk to fish.

 

[10 Tanks]

Just throwing in my two cents…. I change water about once a month, roughly 25% in most of my tanks which are lightly populated (70%) and heavily planted. I feed the inhabitants lightly every other day. The only deaths I’ve had recently was a 3 day power outage in the winter before we got our generator to provide life support to our aquariums and our refrigerator/well pump.

One of the tanks I’m referring to is an open top aquarium that that tank takes 3 gallons of new RO water weekly. I never see nitrates over 10ppm in that tank. (30 gallon - 1 angel, 1 SAE, 3 Kuhli loaches, 5 neons) Yes, lower than recommended loaches/neons to winter power outage deaths. Water got very cold.

The larger tank has a lid and doesn’t have as much evaporation. 38 gallons - 3 cories, 1 SAE, 4 glass cats and 17 ember tetras. This tank usually needs more water changes than the other two tanks.

Your guppy problem could have several factors. They’re often overbred and inbred so genetics can play a role, weakened stock. If they are multiplying quickly it could have something to do with the water or other substances getting into the water (freshly soap-washed hands, lotions, cleaning sprays used nearby, etc…). Perhaps one became sick and now it is working its way through the school on the weaker guppies.

Good luck with the tank and I hope your daughter enjoys the wonderful hobby of fish keeping.

Hello. Fish are extremely adaptive. Your fish a

 

[10 Tanks]

Just throwing in my two cents…. I change water about once a month, roughly 25% in most of my tanks which are lightly populated (70%) and heavily planted. I feed the inhabitants lightly every other day. The only deaths I’ve had recently was a 3 day power outage in the winter before we got our generator to provide life support to our aquariums and our refrigerator/well pump.

One of the tanks I’m referring to is an open top aquarium that that tank takes 3 gallons of new RO water weekly. I never see nitrates over 10ppm in that tank. (30 gallon - 1 angel, 1 SAE, 3 Kuhli loaches, 5 neons) Yes, lower than recommended loaches/neons to winter power outage deaths. Water got very cold.

The larger tank has a lid and doesn’t have as much evaporation. 38 gallons - 3 cories, 1 SAE, 4 glass cats and 17 ember tetras. This tank usually needs more water changes than the other two tanks.

Your guppy problem could have several factors. They’re often overbred and inbred so genetics can play a role, weakened stock. If they are multiplying quickly it could have something to do with the water or other substances getting into the water (freshly soap-washed hands, lotions, cleaning sprays used nearby, etc…). Perhaps one became sick and now it is working its way through the school on the weaker guppies.

Good luck with the tank and I hope your daughter enjoys the wonderful hobby of fish keeping.

Hello. You've got an unusual situation. Apparently, you have very adaptive fish. Your fish have become accustomed to less than optimum water conditions and in this case an attempt at cleaning up the water would create such a sudden change in water conditions that the change would be fatal to them in just a short time. I wonder how the life expectancy of your fish would change if you very gradually worked up to the point you changed half or more of the tank water weekly or even a bit more often??

10 Tanks (Now 11)

 

[Aqua67]

I used to change weekly but sometimes I can’t due to my job. For example, I’ll be gone from 9//24 to 10/10 and won’t be able to do any water changes. I’m always testing the water, including a TDS meter. I keep things monitored and in great shape.

 

[Hmarie37]

It depends on your bio load on your tank. All tanks are different. Just because someone does "X" amount of gallons every week on their tank, doesn't automatically mean that that is the right level for you. Far from it.

It's all about monitoring your nitrate and doing your water changes when it reaches a certain level of acceptability. And bear in mind that each hobbyist has their own ideas of what level of nitrate is acceptable. But generally speaking I think most of us would go along with 20ppm as a max.

So, when your nitrate reaches 20ppm, do a water change. 50% w/c will reduce nitrate to 10ppm, 75% w/c will reduce nitrate to 5ppm, and so on and so forth, simple maths.

Then you need to measure how long it takes go get up to 20ppm again, and repeat your w/c schedule, and so it continues. Over a period of time you will get into a routine, and you will know exactly when to change your water, and how much.

Feeding heavily and overstocking can increase nitrate creep meaning you need to perform more frequent and/or bigger water changes.

This this this!^^^

 

[10 Tanks]

I used to change weekly but sometimes I can’t due to my job. For example, I’ll be gone from 9//24 to 10/10 and won’t be able to do any water changes. I’m always testing the water, including a TDS meter. I keep things monitored and in great shape.

Hello again. What you're apparently able to do with the water goes against all my years of studying water chemistry and working on optimum water change routines and equipment for keeping the tank water virtually nitrogen free. I'm not going to try and understand it, but I'm glad it works for you.

10 Tanks (Now 11)

 

[Byron]

All I am going to add at this juncture is, that the opposing "views" are missing a few facts. First, there is stuff in the water that we cannot measure, and the only way to remove it is a water change. The TDS is a better tool, yes. Those using nitrate readings are going too long without action if nitrates increase substantially. But, nitrate is one factor, and not the only one.

 

[AlexT]

All I am going to add at this juncture is, that the opposing "views" are missing a few facts. First, there is stuff in the water that we cannot measure, and the only way to remove it is a water change. The TDS is a better tool, yes. Those using nitrate readings are going too long without action if nitrates increase substantially. But, nitrate is one factor, and not the only one.

Can a TDS measurement tell us what is bad TDS and what is not? Can it differentiate? Or is all TDS bad? When I say bad, maybe I mean "less ideal" or "unwanted".

 

[Byron]

Can a TDS measurement tell us what is bad TDS and what is not? Can it differentiate? Or is all TDS bad? When I say bad, maybe I mean "less ideal" or "unwanted".

An article I did for another forum some years ago may help explain this. It is online on our member @AbbeysDad blog, here:

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