Nitrogen Control for Healthier Fish

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BBradbury

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Hello. I've found that nitrogen poisoning is the main cause of fish deaths. If you can remove the nitrogen from the tank water before it builds up, you can have fish that live years beyond the life span you read about. So, what is nitrogen and how do you keep it out of the fish tank? Nitrogen is mostly produced from dissolving fish waste. You can remove it by removing and replacing most of the tank water roughly every five to seven days. You also need to monitor the amount of food you give your fish. A pinch or two every day is typically enough. A fish stomach is about the size of one of its eyes, so a little food is enough for a day. Breeding fish may require a bit more, but not much. The fish I've kept have reproduced well on a little food given every day. Regular, large water changes are the reason I have six year old Tetras, eight year old Corydoras and Plecos, Guppies that live four years and Danios that are almost four. The hobby should really be called "The Water Keeping Hobby". Just change the water.

B
 
Hello. I've found that nitrogen poisoning is the main cause of fish deaths. If you can remove the nitrogen from the tank water before it builds up, you can have fish that live years beyond the life span you read about. So, what is nitrogen and how do you keep it out of the fish tank? Nitrogen is mostly produced from dissolving fish waste. You can remove it by removing and replacing most of the tank water roughly every five to seven days. You also need to monitor the amount of food you give your fish. A pinch or two every day is typically enough. A fish stomach is about the size of one of its eyes, so a little food is enough for a day. Breeding fish may require a bit more, but not much. The fish I've kept have reproduced well on a little food given every day. Regular, large water changes are the reason I have six year old Tetras, eight year old Corydoras and Plecos, Guppies that live four years and Danios that are almost four. The hobby should really be called "The Water Keeping Hobby". Just change the water.

B
I know you mean well and this subject has been debated Ad Nauseam but the fact of the matter is that a fish's stomach is not the same size as it's eyeball. This has been " the story" almost as long as the 1" of fish per gallon theory has been around, and we know how false that one is, but neither is true 100% of the time. I just returned from a fishing trip where I was cleaning fish every day looking at stomach contents plus the fact that I routinely did autopsies on pet fish so I have an " inside" few of the facts. ;) 1751563882182.png Here's another view with labels 1751566160084.pngand you can clearly see this fish's stomach is much larger than it's eyeball: Different fish have different stomach sizes. The average stomach can range from 1 cm to 10 cm+. PLUS, a fish's stomach has the ability to expand to accommodate a certain amount of food so while a "pinch" of food might be enough food to satisfy your fish, it may not satisfy another's fish for various reasons such as more fish in their tank, larger fish in their tank, more voracious feeders or less fish than you have so even a pinch may be overfeeding. ( Also, your pinch might not be the same as my pinch which may not be the same as a child's pinch which may not be the same as an adult's pinch. )I've found over the decades that a better method of gauging food amount is time it takes to eat it. It's been found that multiple feedings per day will keep a fish healthier than one meal per day. By using the timing method, you don't over stuff the fish and you also don't starve fish that weren't fast enough to get the food available at the last feeding. The recommended time frame is 1-2 minutes for smaller fish or 3-4 minutes for larger fish, 2 to 3 times per day, so you want to measure how much food is being consumed in these time frames. In actuality, you can feed fish any number of times per day with the caveat being that the amount of food fed per feeding gets smaller the more frequently you feed. At the end of the day of smaller feedings more often, your fish should have consumed more food than from just that one feeding while the filtering and scavenging of the fish should keep the water from getting polluted.

Where you are 100% spot on track is keeping the water clean. (y) (y) Yes, the more frequently you feed, the more ammonia is being produced which will eventually be turned into nitrates in a fully cycled aquarium. This is why routine water changes are so important but it's not just to reduce nitrates ( another common misconception) but to replenish the minerals and vitamins and other chemicals in the water the fish are absorbing out of the water as well. As the saying goes, "Dilution is the solution to the pollution." ;)

Hope this helps. (y)
 
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Hello Andy. That's the information I've gotten from my research. I'd really have a hard time believing a fish the size of those I keep would have a stomach much larger than one eye. Of course, I'm talking about the majority of tropicals people have in their fish tanks. The main point of my post was to encourage the readers not to feed their fish too much and to perform large, frequent water changes.

B
 
Hello Andy. That's the information I've gotten from my research. I'd really have a hard time believing a fish the size of those I keep would have a stomach much larger than one eye. Of course, I'm talking about the majority of tropicals people have in their fish tanks. The main point of my post was to encourage the readers not to feed their fish too much and to perform large, frequent water changes.

B
I get that and applaud you doing the research. As I stated, your info on needing to be changing water is right on target. (y) For some reason, doing water changes in a fish tank has become a " bug-a-boo" that people do everything they can to not do them :facepalm: and yet the majority of a fish's health is based on the quality of the water it's living in. The issue is that your are assuming everybody has the same fish and that your feeding schedule and food amounts will work for anyone reading your post. The problem is that that is just not true, as I pointed out in my response. There are also cases where large volume water changes are not suggested because some fish just don't handle drastic change. ( I've killed enough fish to know this to be true. :( ) In some cases, daily smaller water changes have a greater success rate than large volume ones do. I believe we've had this conversation before but in many cases, if you haven't started with doing large changes from the start, doing them when the water parameters are so different kills fish more than helps them. I'm not saying they are a bad thing but just more explanation as to HOW and WHEN to do them should be part of your responses. This info is not opinion, it's proper husbandry practices. It's no different than letting a new puppy or kitten get used to being in a new home before handling it vs everyone in the home handling the new pet aggressively and just freaking the pet out. You don't want to freak the pet out. That's good husbandry. Good animal husbandry has parameters based on the animal specie, which is not universal to all animals.
As for food amounts, here's a great reason why the " pinch" method of feeding is not universal: Add the same amount of food to a tank with 25 bumblebee gobies and to a tank with 25 swordtails. I guarantee you that you are either overfeeding the gobies OR underfeeding the swordtails. As I said, your pinch may suit your fish but not necessarily anyone else's tank. Even a tank full of adult BA Tetras will eat more than a tank of young BA Tetras of the same quantity.
If we are trying to help future hobbyists, we need to give them more information, not less. If I learned anything working in different pet stores, it's that there are no definite universal answers that fit every situation. The word "should" needs to be stated vs "will". I.e. "Based on this experience, by doing this and this and/or that SHOULD yield the same results." Keep in mind, not every fish has " read the book." ;) I have a buddy who raised 500 Oscars in a 90 gallon tank from fry to 3 inches each. He did it by changing 90-100% of the water every day from day one. Look at how many people have issues trying to keep 1 or 2 Oscars in a 75 gallon tank. They do a large volume water change when the nitrates are, say, 70 ppm or more and the fish die off or get sick. Why? Because they weren't used to large changes.

Bottom line, all I'm saying is that it's great you are giving advice based on your experience(s) but your explanations really should be more expansive and instructive. Remember, water is not the same everywhere. It's why there are different acclimation methods for different species, different fish that live better in some water than other water and why, especially with so many fish coming in the mail vs from the local fish shop, you can't compare one to the other. You just can't treat all fish the same. ( But it would be great if only we could. (y) )
Hope this helps. (y)
 
Both you guys make excellent points. It seems that B. provided the "Outline" and "Andy" completed the "Novel:. Lol.

Plenty of theoretical and verifiable information was provided that should prove benificial for most readers.

It's really good to let the inexperienced know that this wonderful hobby isn't so much about fishkeeping as much as it is about water management.

I don't think B. was trying to fill in the blanks regarding the total scope of fish keeping. Just trying to provide a general guide for success.

Good conversation guys.
 
Both you guys make excellent points. It seems that B. provided the "Outline" and "Andy" completed the "Novel:. Lol.

Plenty of theoretical and verifiable information was provided that should prove benificial for most readers.

It's really good to let the inexperienced know that this wonderful hobby isn't so much about fishkeeping as much as it is about water management.

I don't think B. was trying to fill in the blanks regarding the total scope of fish keeping. Just trying to provide a general guide for success.

Good conversation guys.
Sadly, there is a a lot, A LOT of bad information online which is why, I feel, it's up to us advanced, experienced , long time fish keepers... to take the lead in advising new fish keepers. The good part with the internet is that it opens up the information to a wider audience. The bad part is that it opens up the posting of information to come from anyone whether they have experience or not. Add to that that someone's experience in say, NJ, which has/had soft acidic water is not going to be the same in say, FL, where the water can be very hard to very soft and very acidic to very alkaline depending on where in the state the person is. ( FYI, I live/lived in both of these states and brought fish from one to the other so this is not hyperbole information but actual experience. ) Also, the majority of the information online, from even reliable sources ( i.e. fishbase, Seriously fish, etc), is information on wild caught fish while most of what we have available in the hobby are farmed raised fish so their natural habits ( i.e. water parameters, foods, etc.) are not necessarily what the farmed fish are living in. So in reality, the internet has become a relatively useless source of information for much of fish keeping while the place a person is getting their fish or livestock from should be where the information on parameters should be coming from. But who would know that? The experienced keepers should. (y)
In reality, fish keeping can be as easy or as complicated as the hobbyist wants to make it. That said, not all fish will respond well to the " easy" way and not all fish will require the "complicated " way. You can't expect a Discus to do well in a 10 gallon tank and you shouldn't expect a crowntail Betta to do well in a large tank with high water flow. Neither one will have a happy result.
The bottom line is that fish keeping requires knowledge just like the keeping of any other pet. Unfortunately, some of that information is somewhat complicated but is necessary to know so there are no short answers for all the questions. Sadly, we now have stores ( no names in particular but we know which ones I mean ;) ;) ) with salespeople giving out bad , not poor but BAD, information for the sake of a sale. That shouldn't be acceptable IMO but I'm admittedly biased as I worked in a number of Mom & Pop shops where I was grilled by owners to know what the heck I was talking about before I was allowed to talk to customers. ( Fortunately for me, I was already more experienced than most of the owners before I was offered the jobs. ;) :brows:)

So as you see just in my responses, short answers are not in my nature. ;) That's because I want people to know it all, not just some of the information because lives are at stake. I get no joy from hearing from people anywhere, online of offline, that their fish died and often when they tell me what they did, my first reaction is :facepalm: because of what they were told to do. We can blame the fish and we can blame the products we have available but the real blame is the lack of knowledge.

Hope this helps. (y)
 
Hello again. I think the eye size for the typical tropical fish from the store is pretty accurate. If the human body is any indication, a heart is the size of a fist and the brain maybe a bit larger than two fists.

B
 
Hello again. I think the eye size for the typical tropical fish from the store is pretty accurate. If the human body is any indication, a heart is the size of a fist and the brain maybe a bit larger than two fists.

B
I'm just trying to tell you that autopsies I've done plus dissections done in labs show that's wrong. This pic I posted was from one of my Angelfish that got Dropsy. When I exposed the abdominal cavity, it was full of fluid. You can clearly see how much area was open for the stomach to expand into. So the eye comparison may be close when the fish has no food but not when it's fed. And when it's fed, the stomach has the capacity and space to expand to a much larger size. Sorry but the facts are the facts, whether you believe them or not. ;) If that's not enough for you, here's the internet's response to the question: " Is a fish's stomach the size of it's eyeball?"


No, a fish's stomach is generally not the same size as its eyeball. While the stomach of some fish, like Betta fish, is often described as being about the size of their eye, this is a general guideline for feeding, not a universal anatomical measurement, according to fish care guides. The stomach size can vary significantly between different species of fish and even within the same species depending on factors like diet and age. Some fish have no stomach at all, according to a fish anatomy manual.

Here's why the "eyeball size" comparison is used:
  • Feeding Guideline:
    It's a simple way to help aquarium owners understand how much food to give their fish. Overfeeding can be harmful to fish.

  • Stomach Variation:
    Fish stomachs can be quite small, especially in species that eat small, frequent meals. For these fish, the stomach's capacity might be roughly equivalent to the size of their eye.

  • Generalization:
    The eyeball size comparison is a simplification. Some fish, especially larger predatory species, have much larger stomachs.

    I can't give you any more solid evidence of it's falsity. :flowers: And here's the answer to the question of "how large is a human stomach?" if we are going to use human references: The stomach of an adult is about the size of a fist. This organ has the ability to expand as much as 40 times its original size in order to hold a big meal or large fluid intake. ( So if a human stomach can expand, so can a fish's stomach. 🤔 )
 
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Guys, I think we can all agree that large weekly water changes are the key to a healthy aquarium environment and the best method for disease prevention. The issue is what constitutes "Large".

B. recommends at or near a 100% weekly water change. If that works for B. That's great. That's roughly 400% of the water changed out monthly.

My primary tank is only a 120 gal. Most would consider it overstocked, housing nearly 100 fish, various Barbs, Danios. Loaches & BA Tetras.

My fish become stressed with a solo 50% weekly water change. It takes a couple of days after such a change for their normal behavior to return. I believe a 100% weekly WC might actually be detrimental, at least in my situation.

Two separate 25% weekly water changes seem to work out better. The natural behaviors of the fish aren't disrupted this way.

This water change schedule works out to approximately 200% monthly, which is half of what B. makes. It's still quite a lot of water exchanged, 200+ gallons.

I continue to use 5 gal. buckets, Lol, to make water changes. I'm too old and hard headed to evolve to a more sensible method.

I also keep very long lived fish and rarely have any disease issues.

There are those who practice the so called perpetual non- maintenance method. Tanks with no water changes, which only require top offs due to evaporation.

I call those setups, green water swamp tanks. Lots of plants, a few tiny fish, snails, bugs & worms. Definitely not for me and probably not for most aquarist either.

It seems that several years ago, quite a few fishkeeping YouTubers promoted the self sustaining swamp tanks. Don't see too many promoting that method anymore.
 
Guys, I think we can all agree that large weekly water changes are the key to a healthy aquarium environment and the best method for disease prevention. The issue is what constitutes "Large".

B. recommends at or near a 100% weekly water change. If that works for B. That's great. That's roughly 400% of the water changed out monthly.

My primary tank is only a 120 gal. Most would consider it overstocked, housing nearly 100 fish, various Barbs, Danios. Loaches & BA Tetras.

My fish become stressed with a solo 50% weekly water change. It takes a couple of days after such a change for their normal behavior to return. I believe a 100% weekly WC might actually be detrimental, at least in my situation.

Two separate 25% weekly water changes seem to work out better. The natural behaviors of the fish aren't disrupted this way.

This water change schedule works out to approximately 200% monthly, which is half of what B. makes. It's still quite a lot of water exchanged, 200+ gallons.

I continue to use 5 gal. buckets, Lol, to make water changes. I'm too old and hard headed to evolve to a more sensible method.

I also keep very long lived fish and rarely have any disease issues.

There are those who practice the so called perpetual non- maintenance method. Tanks with no water changes, which only require top offs due to evaporation.

I call those setups, green water swamp tanks. Lots of plants, a few tiny fish, snails, bugs & worms. Definitely not for me and probably not for most aquarist either.

It seems that several years ago, quite a few fishkeeping YouTubers promoted the self sustaining swamp tanks. Don't see too many promoting that method anymore.
You are the perfect example of why B's method is not the universal answer and why I keep pushing against it. It's not the best for all situations and it very easily can kill fish or other aquatic life. There are a lot of " as long as"s and "If X and Y is true"s in order for that method to be advisable. In fact, Loaches happen to be one fish family that it's not advisable for which is ironic because most of them come from flowing rivers and streams and you point out your fish, including loaches, don't handle even a 50% water change well. WEEKLY WATER CHANGES is definitely a universal method but the how much is all dependent on the fish species being kept and the number of changes per week will also depend on the load and it's effects on the water chemistry. There are a number of ways to keep fish for sure and I don't often " argue" against other methods but large water changes is something I'll always advise people to be extra cautious doing and to do a lot of research on their fishes before doing them. There is also another issue which rarely gets mentioned and that is the fact that many fish keepers are not on wells and municipalities can be doing pipe cleanings or chemical washes that in small doses, the fish ( actually the water conditioner) may be able to handle but not in large doses. We in S. Florida went through this when the area went from chlorine to chloramine without any notification. Many stores, including the one I was working in at the time, lost their stock and it took a lawsuit by the pet industry to get them to send out advisories to the pet stores 30 days before a scheduled pipe flushing or cleaning so that we could take precautions and advise our customers to not change water on those days. So there are some strong downsides to large volume water changes that just don't exist with smaller volume changes.

As for still using 5 gal buckets on a big tank, I have much respect. ;) (y) My back gave out decades ago so I am forever designing water systems that do the changing from valves instead of backs. ;) It also helps keeping multiple tanks at one time more convenient. (y)

As for the no water change methods, there was a gentleman in Florida who designed one of the systems that used a certain type of filter to remove nitrates. At a club auction, I saw some of the fish he was selling. Discus, Angelfish, Catfish, Rams were all being auctioned off. Not one of his fish wasn't a dwarf. 5 year old Discus that were the size of a "medium" wild caught Discus. ( And these were breeding pairs so you know they weren't young fish.) I happened to visit a fellow member of another site I was on in West Virginia during one of my trips and he showed me some Discus that he bought from this same gentleman. These too were also stunted. So there are definitely more reasons for changing water than just nitrate control. THAT, I believe, we all can agree on. (y) :)
 
That is a coincidence. Chlorine is typically used by my rural water department.

If money runs low, I get a notice from the water dept. stating that Chloramine will be temporarily used. I guess it's a less expensive chemical.
 
That is a coincidence. Chlorine is typically used by my rural water department.

If money runs low, I get a notice from the water dept. stating that Chloramine will be temporarily used. I guess it's a less expensive chemical.
Wow!!! Chlorine is so " Old School" ;) ;) :lol: I much prefer chlorine to chloramine. You can just let the water sit with an air stone overnight and it was good to use. You can't do that with chloramine. :(
 
I live in an old school Oklahoma rural neighborhood. Lol. Chlorine is how it's always been done here. Things are slow to change in my little town and that's a good thing.
 
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