Losing my nitrate battle

[Wills]

The UK, like the EU, has a legal limit of 50ppm. IMO that's too high for human or animal consumption. But we know that removing nitrate is costly so the water companies only do what they MUST. In my area we get ground water and it's heavily forested - so really not surprising it comes out of the tap at 50ppm

Indeed, would be terrible if the UK had pretty unscrupulous water companies and a government about to rip up any legacy EU regulations.

Wills

 

[GaryE]

This is editorializing so feel free and maybe obliged to not read. But this is a fishkeeping nightmare bind you guys are in. A family member moved out to the prairies, where the deer and the antelope play, and there is no drinkable water outside the grocery store because of mega-farming. She can't even consider a fishtank. I knew that drinking water pollution was a problem through the Canadian prairie provinces into the US midwest, but the UK wrinkle is newish to me. I only learned about it here.

Sometimes our little hobby can open windows into large issues and problems.

 

[ChasingFish]

Am I just crazy? Are we really talking about NITRATE levels of 40ppm being too high? I am reading from the previous posts that this is poisonous to fish and that aquatic plants don't lower the nitrate, when I was under the impression that 40ppm is not a dangerous level and that aquatic plants DO utilize nitrate which is why having a lot of them is so beneficial to stabilizing your tank.

I know that even moderate amounts of ammonia and NITRITE are dangerous for fish, but I seriously believe that nitrate in those low amounts is not something to worry about. All of my 12 tanks regularly test at 40ppm nitrates, or slightly less and I have not seen serious problems with my fish health or die off. It's unfortunate that you are dealing with that in your tap water, and I wouldn't be happy about it either, but I don't think it's an unmanageable situation.

More experienced people here, am I totally wrong?

 

[ChasingFish]

https://www.fdacs.gov/Consumer-Reso...um-Fish/Aquarium-Water-Quality-Nitrogen-Cycle

Nitrate​

Nitrate is formed from the breakdown of nitrite by nitrifying bacteria. Except in very high concentrations, nitrate is not toxic to most freshwater fish. Nitrate can be absorbed by plants or removed from the water through periodic water changes. In natural systems and some aquarium systems, nitrate is converted to nitrogen gas by denitrifying bacteria.

Nitrogen Gas​

Nitrogen gas can be produced in the aquarium from the conversion of nitrate. However, it is often of more concern in some underground source waters, particularly water from wells and springs, where nitrogen may be at supersaturated levels. As with oxygen and carbon dioxide, the solubility of nitrogen increases with decreasing temperature and salinity and increasing pressure. The pressure reduces as water from a well or spring reaches the surface and less nitrogen gas can be held. If this water is put directly on fish, bubbles can form in the gills, skin and fins as the nitrogen begins to vent off in an attempt to equalize with the nitrogen in the atmosphere. This problem, known as Gas Bubble Disease, is similar to the bends in divers and can cause death if the condition is severe. Well or spring water should be degassed before coming into contact with fish. Vigorously aerate the water with an air pump and airstone for approximately 24 hours before the water is added to the tank to ensure excess nitrogen gas has been removed. <--(Perhaps this is the actual problem??)

 

[seangee]

Am I just crazy? Are we really talking about NITRATE levels of 40ppm being too high? I am reading from the previous posts that this is poisonous to fish and that aquatic plants don't lower the nitrate, when I was under the impression that 40ppm is not a dangerous level and that aquatic plants DO utilize nitrate which is why having a lot of them is so beneficial to stabilizing your tank.

I know that even moderate amounts of ammonia and NITRITE are dangerous for fish, but I seriously believe that nitrate in those low amounts is not something to worry about. All of my 12 tanks regularly test at 40ppm nitrates, or slightly less and I have not seen serious problems with my fish health or die off. It's unfortunate that you are dealing with that in your tap water, and I wouldn't be happy about it either, but I don't think it's an unmanageable situation.

More experienced people here, am I totally wrong?

When I accepted that viewpoint I was convinced that the average lifespan of the fish I keep was 12-18 months. I met a fellow fish keeper at dinner (by accident). We discovered that we keep the same fish but he reckoned his average lifespan was 6-8 years. We became friends and compared our tank parameters regularly. Nitrate levels were the only difference. That was my main reason for switching to RO water. Now I no longer have an annual fish replacement budget and losing fish (to old age) is a rarity. Too early to tell but I would agree with his 6-8 years average.

It depend on whether your idea of poisonous is it kills them quickly or it reduces their lifespan.

 

[Wills]

Am I just crazy? Are we really talking about NITRATE levels of 40ppm being too high? I am reading from the previous posts that this is poisonous to fish and that aquatic plants don't lower the nitrate, when I was under the impression that 40ppm is not a dangerous level and that aquatic plants DO utilize nitrate which is why having a lot of them is so beneficial to stabilizing your tank.

I know that even moderate amounts of ammonia and NITRITE are dangerous for fish, but I seriously believe that nitrate in those low amounts is not something to worry about. All of my 12 tanks regularly test at 40ppm nitrates, or slightly less and I have not seen serious problems with my fish health or die off. It's unfortunate that you are dealing with that in your tap water, and I wouldn't be happy about it either, but I don't think it's an unmanageable situation.

More experienced people here, am I totally wrong?

I can totally see where you are coming from and a lot of people will keep fish well in 40ppm + water and not know but when you look into it based on the evidence we are lucky to get from members like Byron and Sean its well worth paying attention to. I've not lost any fish to this in the last 2 years (I've had other issues but not linked to this) but its something I want to address as I develop my hobby as I know it's of benefit to me and the fish.

Aquatic plants will use nitrate as a food source but they will take ammonia first which is abundant in our tanks because of how the fish are kept. Over time heavily planted tanks will take up more ammonia than the filters or at least a 50/50 split, so then the plants are fed with ammonia and don't use the nitrate which is why the nitrate disappears which is great if your water change is done with 0ppm nitrate but if you have 20-40ppm nitrate it's going to just add to what you have already and your aquatic plants won't use it because they have a source of ammonia. This is where terrestrial plants (common ones are mini monstera and pothos but there is a pretty good range of them now), use the nitrate before they use the ammonia so if you have a tank 'filtered' by plants and not getting any nitrate increases week to week the terrestrial plants will take up any nitrates you add during a water change.

But what we don't know is, what will happen to the fish in the time it takes the plants to take up the nitrates - its only low levels maybe 5-15ppm but as Seangee pointed out the issues with nitrate are they are a pollutant that can shorten their lifespan. I always think of it a bit like smoking, day to day not going to really see an issue but over a period of time health issues will likely occur.

Wills

 

[ChasingFish]

I can totally see where you are coming from and a lot of people will keep fish well in 40ppm + water and not know but when you look into it based on the evidence we are lucky to get from members like Byron and Sean its well worth paying attention to. I've not lost any fish to this in the last 2 years (I've had other issues but not linked to this) but its something I want to address as I develop my hobby as I know it's of benefit to me and the fish.

Aquatic plants will use nitrate as a food source but they will take ammonia first which is abundant in our tanks because of how the fish are kept. Over time heavily planted tanks will take up more ammonia than the filters or at least a 50/50 split, so then the plants are fed with ammonia and don't use the nitrate which is why the nitrate disappears which is great if your water change is done with 0ppm nitrate but if you have 20-40ppm nitrate it's going to just add to what you have already and your aquatic plants won't use it because they have a source of ammonia. This is where terrestrial plants (common ones are mini monstera and pothos but there is a pretty good range of them now), use the nitrate before they use the ammonia so if you have a tank 'filtered' by plants and not getting any nitrate increases week to week the terrestrial plants will take up any nitrates you add during a water change.

But what we don't know is, what will happen to the fish in the time it takes the plants to take up the nitrates - its only low levels maybe 5-15ppm but as Seangee pointed out the issues with nitrate are they are a pollutant that can shorten their lifespan. I always think of it a bit like smoking, day to day not going to really see an issue but over a period of time health issues will likely occur.

Wills

That makes sense, thank you for the explanation. I'll have to look into this more!

 

[Byron]

Am I just crazy? Are we really talking about NITRATE levels of 40ppm being too high? I am reading from the previous posts that this is poisonous to fish and that aquatic plants don't lower the nitrate, when I was under the impression that 40ppm is not a dangerous level and that aquatic plants DO utilize nitrate which is why having a lot of them is so beneficial to stabilizing your tank.

I know that even moderate amounts of ammonia and NITRITE are dangerous for fish, but I seriously believe that nitrate in those low amounts is not something to worry about. All of my 12 tanks regularly test at 40ppm nitrates, or slightly less and I have not seen serious problems with my fish health or die off. It's unfortunate that you are dealing with that in your tap water, and I wouldn't be happy about it either, but I don't think it's an unmanageable situation.

More experienced people here, am I totally wrong?

For years this was the thinking of those in the hobby. There were no real scientifically-based studies of the affect of nitrate on aquarium fish; the few studies there were had to do with food fish being commercially raised in ponds and the conditions were extreme, for example, seeing at what level of nitrate trout would all die from within days. You cannot carry that thinking across to ornamental fish.

Ammonia, nitrite and nitrate are all poisonous to aquarium fish. Unlike ammonia and nitrite which tend to act quickly in debilitating and killing fish, with nitrate the level of nitrate, the fish species and age, and the exposure time all factor in. I had a discussion with Neale Monks and Bob Fenner a couple years ago, and after Bob's death the conversation continued with Neale. Neale commented that the best way to think of nitrate's effect on aquarium fish is to consider it a weakening of the fish, which in time always results in a shorter lifespan because the fish become more susceptible to other problems that without the nitrate would not be "problems." In the fish, nitrate will act much like nitrite, making it more difficult for the blood to carry oxygen. Fish such as all cichlids and mollies are now known to be very sensitive to nitrate, and nitrate is frequently the cause behind hexamita (hole in the head), Malawi bloat, and shimmies. And it adds stress to the fish.

This should seem logical to all of us, when one remembers that in their habitat waters nitrate like ammonia and nitrite are basically zero.

 

[Byron]

Really great info but not quite answered what I meant to ask sorry.

If all the nitrate is dealt with in a tank and taken to 0-5ppm by terrestrial and aquatic plants - presuming they are taking care of phosphate and some other organics as well. Do you think a 50% water change is still necessary (assuming sensible stocking levels) or would something in the region of 25% be a good option? This way in my situation I would be raising the nitrate level to between 6 and 11ppm at a water change (from 0-5ppm). Or if I did 50% it would take it to 12.5-16.5ppm.

I think terrestrial plants are the only way to reduce nitrates in a tank like @seangee said growing aquatic plants means they take up the ammonia so nitrate isn't produced so the way the terrestrial plants use nitrate as a food source is the only way I think to actually reduce it. It takes about 10-12 weeks for them to do anything but once the aquatic root systems get going you really see the difference in levels I have some problems in my current tanks still but definitely improving.

Its interesting as most people that have problems with high nitrates are usually from the UK, and UK houses are so small compared to other countries we have a hard time storing water in ways that make life easy sometimes...

@Wills I ran this past Neale as promised, and will provide his thinking with which I certainly will not disagree. Assuming the nitrate resulting from the W/C is basically used up as you indicate, by plants for example, and given the low numbers, not a worry. Also depending upon the fish species' sensitivity to nitrate. Except for such fish, assuming the W/C does not result in nitrate much above 10-20 ppm, that's fine. It's continual exposure to non-ideal conditions that seems to be a problem, rather than brief ups and downs within their tolerance range.

Edit: Neale came back with this:

Probably worth avoiding the 50% water changes in this situation. Again, will depend on the fish, but if we're talking a community tank, 25-30% every week or so might well be fine. Moderately stock the tank so the nitrate level doesn't rise too steeply, and should be fine. I'd have thought, anyway!

Byron.

 

[Naughts]

This is editorializing so feel free and maybe obliged to not read. But this is a fishkeeping nightmare bind you guys are in. A family member moved out to the prairies, where the deer and the antelope play, and there is no drinkable water outside the grocery store because of mega-farming. She can't even consider a fishtank. I knew that drinking water pollution was a problem through the Canadian prairie provinces into the US midwest, but the UK wrinkle is newish to me. I only learned about it here.

Sometimes our little hobby can open windows into large issues and problems.

Could be worse ( I average 23ppm from the tap but still have sucess with planted fishtanks).
In India 85% of water supplies are untreated ground or surface waters used in agriculture. This member has 4ppm of ammonia as well as the high nitrates (50-100ppm) :

Help! Cant control water parameters - colour widows (glofish) dying

I had previously started the discussion in another thread but after understanding that the problem is related to water quality, I am starting this new thread with correct topic. I bought my first aquarium (75L) in July 2022 and without cycling put 12 colour widow tetras (glofish) and 2...

www.fishforums.net

 

[raylove]

I use JBL Bionitratex in my filter. The theory is that it creates conditions for the anaerobic bacteria that break down the nitrate. It lasts 6 months so it's cost effective. I too have 30+ ppm in my tap water but my tank is usually around 5ppm.
I used to assume that my plants used up the nitrate until I learned that they use the ammonia before it gets to the nitrate stage which means they probably only prevent additional tank generated nitrate. Even before I used the Bionitratex my tank levels were low at maybe 10ppm but at that time I still used lots of fine porous filter media to encourage nitrate absorbing bacteria. The Bionitratex seems to have boosted the effect - all I can is something is working here!
However, the downside is that big water changes put too much nitrate in for this system to cope with and 15%-20% is the max I can do without upsetting the balance. However, that seems to be enough as the fish thrive and live for many years. From time to time I do a big clean and then I add a nitrate absorbing resin to my filter to get the level down a bit, then the tank does it's magic and low nitrate returns. Using the resin isn't ideal but if I don't do this my plants don't grow well in high nitrate and hence don't deal with the ammonia. Nitrate then cycles upwards and the balance is hard to get back.

 

[Characf]

I use JBL Bionitratex in my filter. The theory is that it creates conditions for the anaerobic bacteria that break down the nitrate. It lasts 6 months so it's cost effective. I too have 30+ ppm in my tap water but my tank is usually around 5ppm.
I used to assume that my plants used up the nitrate until I learned that they use the ammonia before it gets to the nitrate stage which means they probably only prevent additional tank generated nitrate. Even before I used the Bionitratex my tank levels were low at maybe 10ppm but at that time I still used lots of fine porous filter media to encourage nitrate absorbing bacteria. The Bionitratex seems to have boosted the effect - all I can is something is working here!
However, the downside is that big water changes put too much nitrate in for this system to cope with and 15%-20% is the max I can do without upsetting the balance. However, that seems to be enough as the fish thrive and live for many years. From time to time I do a big clean and then I add a nitrate absorbing resin to my filter to get the level down a bit, then the tank does it's magic and low nitrate returns. Using the resin isn't ideal but if I don't do this my plants don't grow well in high nitrate and hence don't deal with the ammonia. Nitrate then cycles upwards and the balance is hard to get back.

I'll look into this, thanks

 

[StevenF]

All plants will consume nitrate including floaters. Unfortunately it takes to processing steps in the plant to consume it. For ammonia only one processingstep is needed. So nitrate absorption is partially a time problem. It takes longer. And you must have no ammonia, urea or any other nitrogen source available to force the plants to work on nitrate.

However there is another issue and that plants cannot aborbe any nitrogen when there is a nutrient deficiency. For the plant to absorb nitrogen it also needs other elements (potassium, calcium, magnesium, phosphorous, sulfur, chlorine, iron, manganese, boron, zinc, bopper molybdenum, and nickel). So if you want to reduce 40ppm of nitrate down to zero you need 4 times of all those other nutrients That means 4 times the micros and macros That is very hard to do with commercial fertilizers and expensive.

As to a cheeper solution you can buy equipment to make distilled water or RO. Yes this stuff is is expensive to buy. But once you buy a RO system the cost to make the RO water is extremely low. I can go 2 years without buying replacement filters. The manufactures recommends changing the filter more often but with my TDS meter it only take a minut to measure the purity of the water and and if the redding is high you replace the filters.

You can buy electric water distillers but they need electricity to run and with then high cost of power right now in europe it would probably be more expensive than what you are doing now. Also for your nitrate filter be sure to use distilled water when when making he salt water solution for the recharge.

 

[Wills]

@Wills I ran this past Neale as promised, and will provide his thinking with which I certainly will not disagree. Assuming the nitrate resulting from the W/C is basically used up as you indicate, by plants for example, and given the low numbers, not a worry. Also depending upon the fish species' sensitivity to nitrate. Except for such fish, assuming the W/C does not result in nitrate much above 10-20 ppm, that's fine. It's continual exposure to non-ideal conditions that seems to be a problem, rather than brief ups and downs within their tolerance range.

Edit: Neale came back with this:

Probably worth avoiding the 50% water changes in this situation. Again, will depend on the fish, but if we're talking a community tank, 25-30% every week or so might well be fine. Moderately stock the tank so the nitrate level doesn't rise too steeply, and should be fine. I'd have thought, anyway!

Byron.

Thanks Byron, I wish Neale would come back to the forum I see him on some facebook groups and he helps me there but does not know its me... if you see what I mean...

I feel like this could be the easiest solution for high nitrate tap water in some senses, making sure the terrestrial plants are dense enough and growing fast enough to use up the water sources, for my big tank I've found some plants grown for decorative purposes in water so they should (in theory) be ready to go from day 1. And then regular but smaller regular water changes to dilute other pollutants not used by the plants. Reduces the risks associated with RO and remineralising.

Could be worse ( I average 23ppm from the tap but still have sucess with planted fishtanks).
In India 85% of water supplies are untreated ground or surface waters used in agriculture. This member has 4ppm of ammonia as well as the high nitrates (50-100ppm) :

Help! Cant control water parameters - colour widows (glofish) dying

I had previously started the discussion in another thread but after understanding that the problem is related to water quality, I am starting this new thread with correct topic. I bought my first aquarium (75L) in July 2022 and without cycling put 12 colour widow tetras (glofish) and 2...

www.fishforums.net

Its not just places like India, in the US we've had members whose tap water is contaminated by stuff like C8 and all the old pipes infrastructure plus what we're going through / going to go through pretty soon in the UK...

I use JBL Bionitratex in my filter. The theory is that it creates conditions for the anaerobic bacteria that break down the nitrate. It lasts 6 months so it's cost effective. I too have 30+ ppm in my tap water but my tank is usually around 5ppm.
I used to assume that my plants used up the nitrate until I learned that they use the ammonia before it gets to the nitrate stage which means they probably only prevent additional tank generated nitrate. Even before I used the Bionitratex my tank levels were low at maybe 10ppm but at that time I still used lots of fine porous filter media to encourage nitrate absorbing bacteria. The Bionitratex seems to have boosted the effect - all I can is something is working here!
However, the downside is that big water changes put too much nitrate in for this system to cope with and 15%-20% is the max I can do without upsetting the balance. However, that seems to be enough as the fish thrive and live for many years. From time to time I do a big clean and then I add a nitrate absorbing resin to my filter to get the level down a bit, then the tank does it's magic and low nitrate returns. Using the resin isn't ideal but if I don't do this my plants don't grow well in high nitrate and hence don't deal with the ammonia. Nitrate then cycles upwards and the balance is hard to get back.

Thats interesting, I've seen a few products like this but never been 100% convinced on how effective they are as de-nitrafying bacteria are anaerobic which means they can't survive in oxygen-rich water which is typically what runs throughout filters but perhaps I'm being a Luddite as there are a lot of people having good success with this kind of media these days.

Wills

 

[seangee]

@Characf since you are in the UK if you want to try RO water take a look at https://www.spotlesswater.co.uk/
Not used them myself but they claim 0TDS and that their water is perfect for aquaria. At 3.5p per litre its a lot cheaper than your LFS - as long as you are prepared to lug containers of water about. (I used to buy it from my LFS until I got fed up with having to drive there every week and lugging 100l of water)