NeonBlueLeon
Fishaholic
Hello folks,
Chemist here. I have had experience with almost all chlorine compounds in the lab, and as a matter of fact, in swimming pools (formerly CPO certified). My exposure to all kinds of chlorine compounds range from minor explosions in the lab, wooziness from inhalation, burned skin, and ruined clothing.
I thought a brief "course" of relevant chlorine compounds would help the community better understand what these chemicals actually are.
Note that some of these chemicals are in fact dangerous, but in terms of what comes out of the faucet, it is on a small enough scale that little harm can befall onto humans. So don't go buying gas masks and heavy duty gloves to put on when turning on the tap.
However, there are enough of these chemicals to harm fishies, which is why we as aquarists have taken interest in these chlorine compounds.
There are four chlorine compounds I want to discuss:
1) Chlorine: Cl2 - When one says "chlorine," the technical meaning is a chlorine molecule. That means two Chlorine atoms bonded together. This stuff is a green gas. It was used in WW1 in chemical trench warfare. When aquarists say "chlorine," they do not mean chlorine gas. More on that later. Chlorine cannot be present in water (would just evaporate out and poison you instead). Needless to say, this stuff is very toxic to breath in, but in terms of aquariums, don't worry about it. Side note: if you see a greenish gas that seems heavier than air coming towards you, run the other way. Just kidding, but not really.
2) Chloride: Cl-- Chloride is the ionic form of chlorine. For any chemistry buffs, it's atomic chlorine with an extra valence electron. This is what table salt is when you dissolve it in water. Similarly, this is also in aquarium salt and, of course, ocean water. Aquarium salt and ocean water have traces other salt compounds in it that are not harmful to fishies. Anyone who treated Ich with salt obviously knows chloride is not harmful to your fish. Even scaled freshwater fish can deal with relatively high levels of salt (aka chlorides) in the water for a temporary period of time. There is no need to remove chlorides from your tap water, and tap water conditioners do not remove it. Note: the effect of chlorides on some invertebrates and scaleless fish is very different.
3) Hypochlorite: ClO-- Now we're talking dangerous for fishies. Hypochlorite is what aquarists and tap water conditioner bottles refer to as "chlorine." This is the stuff found in household bleach, also labeled Sodium Hypochlorite. It is also used in swimming pools, and has the recognizable "chlorine" or bleach smell. In high concentrations, this will eat up virtually anything. Luckily, they don't sell this stuff in high concetrations to the public. The good news is, small amounts of hypochlorite is easily washed away with plenty of water.
However, there are trace amounts of hypochlorite used to keep tap water clear of bacteria and parasites. The main concern of the water department is E. coli strains. Unfortunately, that means after you've bleached your new or quarantine tank and decorations, rinsing with tap water doesn't make it free of hypochlorite. Thankfully, tap water conditioners contain polyvinylpyrrolidone. This is very cool stuff. It is a polymer, much like plastic, but dissolves in water. And it locks up hypochlorites! I mean it literally locks it up into the polymer so it cannot harm your fishies. All tap water conditioners have polyvinylpyrrolidone in it to detoxify hypochlorite.
4) Chloramines: NH2Cl/NHCl2/NCl3 - Oh boy is this stuff really bad for your fishies. With enough of it, it will knock out your fishies' respiratory systems. Do not panic yet, because there is good news. Although some water departments still use chloramines for treatment, most use only hypochlorite. Hypochlorite was found to be about three times as effective, and much less toxic to humans. More good news: chloramines are easily neutralized by sodium thiosulfate, which is found in virtually all tap water conditioners. Prime has the highest concentration of sodium thiosulfate, which is why it smells of sulfur, but other conditioners will work perfectly. Another thing to note is some people may say that carbon will remove chloramines. However, only medical grade carbon can remove chloramines, and not even remotely effectively as sodium thiosulfate. Medical grade carbon is much too expensive and is inaccessible to the average aquarist.
The dangers of chloramines appear when you have ammonia in your aquarium. Ammonia reacts with any and all hypochlorites in the water to form the very dangerous chloramines. So take home lesson about chloramines? Hypochlorites are bad enough, but hypochlorites with ammonia is double-- no quadruple jeopardy!
Some other chemistry notes related to aquariums:
-Some tap water conditioners have EDTA in them. EDTA "locks away" dissolved metals from the water such as iron, copper, and magnesium. The ability of EDTA to lock away chloramines is slow and takes days. EDTA will not affect iron supplements for plants (iron fertilizers are already chelated). Point is, EDTA is not an effective hypochlorite or chloramine remover. I do not know about the toxicity of EDTA in fishies, but it is not a good thing for humans to be over-exposed to. In the old days, EDTA was given to people to drink who had metal poisoning. I personally shy away from conditioners that have EDTA in them.
-Ammonia (NH3) is actually a misnomer. Any ammonia in water would just evaporate out. The ammonia excreted by fish is better known as ammonium (NH4+), which in water has the form NH4OH. In actuality, the relationship of ammonia and water is very complicated and is not easily explained without a chemistry background. This was just for a bit of knowledge for aquarium trivia.
Chemist here. I have had experience with almost all chlorine compounds in the lab, and as a matter of fact, in swimming pools (formerly CPO certified). My exposure to all kinds of chlorine compounds range from minor explosions in the lab, wooziness from inhalation, burned skin, and ruined clothing.
I thought a brief "course" of relevant chlorine compounds would help the community better understand what these chemicals actually are.
Note that some of these chemicals are in fact dangerous, but in terms of what comes out of the faucet, it is on a small enough scale that little harm can befall onto humans. So don't go buying gas masks and heavy duty gloves to put on when turning on the tap.
There are four chlorine compounds I want to discuss:
1) Chlorine: Cl2 - When one says "chlorine," the technical meaning is a chlorine molecule. That means two Chlorine atoms bonded together. This stuff is a green gas. It was used in WW1 in chemical trench warfare. When aquarists say "chlorine," they do not mean chlorine gas. More on that later. Chlorine cannot be present in water (would just evaporate out and poison you instead). Needless to say, this stuff is very toxic to breath in, but in terms of aquariums, don't worry about it. Side note: if you see a greenish gas that seems heavier than air coming towards you, run the other way. Just kidding, but not really.
2) Chloride: Cl-- Chloride is the ionic form of chlorine. For any chemistry buffs, it's atomic chlorine with an extra valence electron. This is what table salt is when you dissolve it in water. Similarly, this is also in aquarium salt and, of course, ocean water. Aquarium salt and ocean water have traces other salt compounds in it that are not harmful to fishies. Anyone who treated Ich with salt obviously knows chloride is not harmful to your fish. Even scaled freshwater fish can deal with relatively high levels of salt (aka chlorides) in the water for a temporary period of time. There is no need to remove chlorides from your tap water, and tap water conditioners do not remove it. Note: the effect of chlorides on some invertebrates and scaleless fish is very different.
3) Hypochlorite: ClO-- Now we're talking dangerous for fishies. Hypochlorite is what aquarists and tap water conditioner bottles refer to as "chlorine." This is the stuff found in household bleach, also labeled Sodium Hypochlorite. It is also used in swimming pools, and has the recognizable "chlorine" or bleach smell. In high concentrations, this will eat up virtually anything. Luckily, they don't sell this stuff in high concetrations to the public. The good news is, small amounts of hypochlorite is easily washed away with plenty of water.
However, there are trace amounts of hypochlorite used to keep tap water clear of bacteria and parasites. The main concern of the water department is E. coli strains. Unfortunately, that means after you've bleached your new or quarantine tank and decorations, rinsing with tap water doesn't make it free of hypochlorite. Thankfully, tap water conditioners contain polyvinylpyrrolidone. This is very cool stuff. It is a polymer, much like plastic, but dissolves in water. And it locks up hypochlorites! I mean it literally locks it up into the polymer so it cannot harm your fishies. All tap water conditioners have polyvinylpyrrolidone in it to detoxify hypochlorite.
4) Chloramines: NH2Cl/NHCl2/NCl3 - Oh boy is this stuff really bad for your fishies. With enough of it, it will knock out your fishies' respiratory systems. Do not panic yet, because there is good news. Although some water departments still use chloramines for treatment, most use only hypochlorite. Hypochlorite was found to be about three times as effective, and much less toxic to humans. More good news: chloramines are easily neutralized by sodium thiosulfate, which is found in virtually all tap water conditioners. Prime has the highest concentration of sodium thiosulfate, which is why it smells of sulfur, but other conditioners will work perfectly. Another thing to note is some people may say that carbon will remove chloramines. However, only medical grade carbon can remove chloramines, and not even remotely effectively as sodium thiosulfate. Medical grade carbon is much too expensive and is inaccessible to the average aquarist.
The dangers of chloramines appear when you have ammonia in your aquarium. Ammonia reacts with any and all hypochlorites in the water to form the very dangerous chloramines. So take home lesson about chloramines? Hypochlorites are bad enough, but hypochlorites with ammonia is double-- no quadruple jeopardy!
Some other chemistry notes related to aquariums:
-Some tap water conditioners have EDTA in them. EDTA "locks away" dissolved metals from the water such as iron, copper, and magnesium. The ability of EDTA to lock away chloramines is slow and takes days. EDTA will not affect iron supplements for plants (iron fertilizers are already chelated). Point is, EDTA is not an effective hypochlorite or chloramine remover. I do not know about the toxicity of EDTA in fishies, but it is not a good thing for humans to be over-exposed to. In the old days, EDTA was given to people to drink who had metal poisoning. I personally shy away from conditioners that have EDTA in them.
-Ammonia (NH3) is actually a misnomer. Any ammonia in water would just evaporate out. The ammonia excreted by fish is better known as ammonium (NH4+), which in water has the form NH4OH. In actuality, the relationship of ammonia and water is very complicated and is not easily explained without a chemistry background. This was just for a bit of knowledge for aquarium trivia.
I ran to the department library and did some searching on chloramines and found some new stuff.
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