Water Parameter FAQ (kind of a rant for me :P)

[punchbuggy]

Hi All,

These osmoregulation, KH, GH, pH, hardness threads have been getting on my nerves… in a good way. Being a Chemistry/Biochemistry major, and doing my PhD in Biochemistry now, I would like to clear up a few inconsistencies in relation to the chemical nature of these terms and actually how they APPLY to life in this case, aquatic life.

So simply, all life depends on energy. We require it to say, have our muscles contract or for chemical reactions to occur. Where do we get this energy? For plants, they consume light and carbon dioxide to produce sugars. These sugars are used up through reactions to generate molecules that are high energy ie. ATP. Animals bypass the light/oxygen part (since we consume sugars) but we still need food (sugars) to make ATP. To make the ATP, cells require an electrical chemical gradient. But that’s a minor part. :P

You might know about our nervous system. How do they work? Through electricity. Where is this energy coming from? IONS. Ions are electrically-charged particles, either atoms or molecules. Ions are what create this gradient that allows for ATP production and for our nerves to communicate.

How should you think about it?

Quite simply, have you ever been shocked by static? Static is due to the fact that one object, has a positive charge and the other negative. Nature likes to equalize things and so the charges move to get both objects neutral. But what if there is a barrier in between (in electrical terms, an insulator)? That keeps the charges apart. Our cells have developed a way to do this and to CONTROL the amount of ions that pass, and harvest the charge movement for useful purposes instead of having the charges jump all at once like a static discharge.

So all this biochemistry talk, what does this have to do with our fishies?!

Well, as you all might know there has been lots of talk on osmoregulation and how BC water is inappropriate for it especially for fish. As well, lots of talk about the conditions for shrimp. Why? Because osmoregulation is the diffusion of water through a cell and its environment. Why is this important? Well everyone here has taken a bath (at least I hope). When you stay in the tub too long, what happens? Your hands and feet get pruney. That is osmoregulation at work. Your cells have a much higher salt concentration and your skin cells have little pores that allow water through. Like most things in nature, water also likes to be equalized (REMEMBER THIS PHRASE). Because there is more salt in your cells, water goes in to try to bring it down to the level it is at in a bathtub (which is not a lot). As a result your skin cells swell.

Now think about this with your fish. Imagine living in an environment like that. NOT FUN going constantly pruney. However, in their case they can’t jump out of the tub and they must ADAPT. Some fish do it better, some fish just die. The way they adapt is the cells change to balance the amount of water and ions to survive in these new water conditions.

As I mentioned, cells use ions to produce energy and to transmit messages through our nerves, amongst other things. These ions have to be a certain level for the processes to be 100%. If a fish has to adapt to conditions where there is say LOW ions (low GH/KH) and so their cells take up water because of the imbalance, this totally disrupts the internal processes that are happening within the cell. Each cell might not be able to divide, produce energy, contract, transmit a message to neighboring cell as efficiently as possible. Fine, your fish might not die, but they are certainly not optimal. They are merely surviving, not thriving. As suggested, the effects might only be seen during times of additional stress. In low ionic conditions, the fish are already adapting. Forcing another stressor makes the cells in the fish completely incapable of coping to a secondary stress.

In terms of shrimp, they experience the same things (huge losses in new tank syndrome) but they also are desperate for certain ions (mainly ones discussed to/referred in GH, or calcium, see below) Any lack of it will be detrimental.

OK you might say, I believe in the importance of ions in this superficial way. But how about the water chemistry. “Someone told me to add x to y but z changed and then x changed so I added p and then y changed” and “Someone said to add this but it didn’t help, but when I did this it helped” are all common. That is because all these processes are connected and are in a equilibrium (balance with each other).

GH

GH is actually the EASIEST to explain. GH, general hardness, is a measure of the AMOUNT by definition of ions with two positive charges, like calcium and magnesium ions. Why two charges? That is beyond the scope here and of no consequence. Our kits use a compound that can bind these ions and produce a colour change that we take as a measure of how much ions there are. Calcium and magnesium are mainly available as salts. Why because salts are essentially ion pairs of positive and negative charges, and you cannot just get ions alone (or else they’ll come clinging on to you and never let go (remember they are charged)).

Typical GH salts are

-Calcium Chloride (CaCl2)
-Calcium Carbonate (CaCO3) (SPECIAL NOTE: for the next section re carbonate)
(note that Magnesium can take calcium’s place)

When added to water the salts split up into its negative and positive parts. In the case of calcium chloride, you will get a calcium ion (positive) and two chloride ions (negative)

The Ca(2+) AND Cl- is what is important in osmoregulation. Also involved in other processes (see above)


KH

KH, gets a bit more complicated. KH is carbonate hardness (also termed alkalinity), and is a measure of carbonate ions. What is carbonate? It is a molecule that holds a charge (Calcium and chloride ions are charged atoms). It is also related to carbon dioxide (SHOCK) and baking soda (GASP).

Here are some formulas for those that are interested.

Carbonate (CO3(2-))

Carbonate + Proton < > Bicarbonate
CO3(2-) + H+ < > HCO3-

Bicarbonate + Proton < > Carbonic Acid
HCO3- + H+ < > H2CO3

Carbonic Acid < > Water + Carbon Dioxide
H2CO3 < > H2O + CO2

Arranged differently

Carbonate + Proton < > Bicarbonate + Proton < > Carbonic Acid < > Water + Carbon Dioxide



So a few things to notice
a) bicarbonate is present in baking soda which is sodium bicarbonate (NaHCO3)
b) CO2 is carbon dioxide

Some things you might think to yourself now
1) OMG what is this proton??
2) OMG carbonic acid becomes water and carbon dioxide
3) OMG when I increase KH (carbonate) I make an acid (carbonic acid), but I don’t want acid I want alkaline!!

So might I answer

1) H+, is known as a proton. It is a charged hydrogen atom. This single ion is responsible for what we know as pH.
2) Yes, yes it does, that’s why you might have heard about pH swings when you inject CO2.
3) Don’t fret, you’re not doing that even though the compound is called an acid.

So to be more in detail

1) pH is a measure of the number of protons, H+. It is a negative logarithmic scale. Science has defined a pH of 7 as neutral. What is netural? Well, water, H2O, is composed of two components

Proton + Hydroxide < > Water
H+ + OH- < > H2O

As I mentioned oh so often before, nature likes a balance. And she likes both sides of this equation. At water’s normal equilibrium, or balance point, there is a certain amount of H+, matched by an equal amount of OH-, matched also by an equal amount of H2O.

To picture this, think of an orange, split it in half and you get both sides of the equation. Now split one of the halves into two. Now you have 2 quarters and one half. But they all add up to be two halves that are equal yet in different forms.

At this point, let me say that we can measure the amount of protons and because it is in water of a certain volume, we know its concentration. If we were to measure the number of H+ at the balance point of water, we obtain a certain concentration. In pH value, that is 7. Remember, this is a NEGATIVE LOGARTHMIC SCALE. The MORE protons you have the LOWER it gets. The LESS protons you have the HIGHER it gets. Also, to get higher or lower than 7, you must have other things that add in more protons, or take them away.

So how does carbonate hardness relate to pH? Well if you look closely at the first part of the formulas, the first line is carbonate. When we add carbonate with H+, it makes bicarbonate. As I mentioned, the amount of protons determines the concentration that determines the pH. If Carbonate uses up a proton to make bicarbonate, the amount of protons go down, and thus the pH goes (QUIZ QUESTION!!!!, correct answer is up).

That is why when we use a product like Seachem alkaline, you will ALWAYS get an accompanying pH increase.

Some might say that they never see this, that they use Seachem alkaline and their KH goes up but the pH doesn’t. I can believe that. Remember, all of this is based on using pure water and then just adding carbonate. If there are things that release more protons into the water (say ADA soil) than in pure water, that will compensate for the loss of protons that combine with carbonate to make bicarbonate.

2) So now, why does CO2 affect KH and pH?
When you inject CO2 most people notice their pH going down. WHY? Well just look at the formulas. The arrows go BOTH WAYS. And what does nature like? BALANCE. The more CO2 you put in, the equation goes backwards (termed La Chatelier principle). What does backwards give you? Carbonic acid. Now go a line up, if you have more carbonic acid, and nature loves to balance, what does that give you? More protons. What are more protons? LOWER pH. You might say, but hey, KH should go up as well. Most people don’t see this and it is mainly because 1) carbonate is converted back to carbonic acid quickly. 2) used up by plants. 3) forms other compounds with other ions.

In addition, this is why “aged” water usually has lower pH. The reason? Water from the tap are in sealed pipes. When we put it in a bucket it is exposed to the atmosphere, an environment with MUCH MUCH more carbon dioxide. This gets dissolved in water and all you have to do is look at the formulas. Some carbonic acid is produced and then just follow the arrows backwards. Theres a point where a H+ pops up by itself. What happens when there are more H+, lower pH…

In general the point is, if you are injecting CO2, some people say to have higher KH. They call this "buffering capacity" Essentially, by having carbonate present AND injecting CO2 at the same time, you are pushing the balance forward in one direction (due to carbonate) and backwards in the other (due to CO2) at the end, because of the two OPPOSING effects, your pH is more stable. This type of push/shave effect is also seen when lights are off in a tank. At night, in a planted tank, the plants stop consuming carbon dioxide and so it builds up. Because of the presence of carbonate, CO2 does not lower the pH swiftly. That is why some people turn off CO2 at night (the other reason is that it is a complete waste since your plants aren't using it since the lights are off).

3) And finally, now eventhough a line in the formulas says acid, it does not mean that will occur. In the above discussion, we are always adding the other compounds (eg carbonate or carbon dioxide) Only when we screw up the natural balance of pure water (injecting CO2, see above #2) will it make your water acidic, because you are pushing all those balances in reverse. If we add carbonate (seachem alkaline, see above #1) you are pushing those balances forward. Only when H+ is free in water does it get more acidic.


So what am I advocating? Nothing. I just needed to do this to clear the air. But I am not pushing any specific KH/GH value. Why? Because different species require different conditions. What I do know is that NOTHING can survive in pure water. There is too much variation from tank to tank to suggest anything (type of substrate for instance). The only thing I would suggest is that people not add tons of chemicals because of their test results. Things are ALWAYS in balance. The more you try to push it in one direction, the HARDER nature will push back to fix it. To finally “force” your condition in a system that does not want to be at that condition, would require so many chemicals your fish will die.

[oakley1984]

+1 to sticky.

[CRS Fan]

Kelvin thanks for this post. I am still not a bio-chemistry major for a reason...... BUT this is informative and your real life examples help to clarify the process. With that being so..... I am still addicted to CO2 (well, at least my plants are) . LOL

Best regards,

Stuart

[Rastapus]

"So what am I advocating? Nothing. I just needed to do this to clear the air. But I am not pushing any specific KH/GH value. Why? Because different species require different conditions. What I do know is that NOTHING can survive in pure water. There is too much variation from tank to tank to suggest anything (type of substrate for instance). The only thing I would suggest is that people not add tons of chemicals because of their test results. Things are ALWAYS in balance. The more you try to push it in one direction, the HARDER nature will push back to fix it. To finally “force” your condition in a system that does not want to be at that condition, would require so many chemicals your fish will die."

punchbuggy,
Thanks for the FAQ. I think all levels of hobbyists can appreciate what you have posted. I am not sure however how to interpret the above quote. Yes, I agree, things always tend to be in balance of some sort but we are maintaining closed systems here where we decide what parameters to run for our particular aquarium habitants. As you said, the fish can't jump out of the aquarium and find what is best for them. Maybe I am misreading the quote but my concern is for those who might read this last part and interpret it as add nothing you will be fine. If our water parameters in the wild were to change drastically, many fish would adjust to the conditions, many would also die. Our water source is closer to "pure water" then any water in Canada, as mentioned, not the best condition for aquarium fish. Before we were adding appropriate buffers at IPU we had many issues with certain species of fish, in particular livebearers and Goldfish. After adjusting the parameters we realized how these low levels were affecting the vast majority of the fish in our care. I found the relative comparisons, particularly the bath good examples. This is not a criticism, just looking out for the masses. Your example of thriving not surviving is the key here to making a change. Great reading.

[kelownaguy]

In addition, this is why “aged” water usually has lower pH. The reason? Water from the tap are in sealed pipes. When we put it in a bucket it is exposed to the atmosphere, an environment with MUCH MUCH more carbon dioxide. This gets dissolved in water and all you have to do is look at the formulas. Some carbonic acid is produced and then just follow the arrows backwards. Theres a point where a H+ pops up by itself. What happens when there are more H+, lower pH…

You are talking about aerated tap water not "aged" water.

From my experience,you have it backwards.
Typicaly,tap water contains more CO2 than an aerated sample of same.
Aerate the water-CO2 is released-pH rises.

"Aged" aquarium water declines in pH because the nitrifying bacteria produce acid and consume kH.
Higher bio-load,lower intial kH and more infrequent water changes(no kH replenishment) give quicker pH drops.


"High rates of ammonia oxidation will acidify the environment and must be neutralized with additions of carbonate alkalinity (e.g., Na2CO3, CaCO3, or K2CO3) since 4 – 7 ppm alkalinity are used for every 1 ppm of ammonia. The enzyme in Nitrosomonas that carries out the first part of ammonia oxidation is inhibited (rendered inactive) by pH less than 7."

From 4 Ammonia in Wastewater Treatment

[punchbuggy]

You are talking about aerated tap water not "aged" water.

From my experience,you have it backwards.
Typicaly,tap water contains more CO2 than an aerated sample of same.
Aerate the water-CO2 is released-pH rises.

"Aged" aquarium water declines in pH because the nitrifying bacteria produce acid and consume kH.
Low intial kH and infrequent water changes(no kH replenishment) give quicker pH drops.


"High rates of ammonia oxidation will acidify the environment and must be neutralized with additions of carbonate alkalinity (e.g., Na2CO3, CaCO3, or K2CO3) since 4 – 7 ppm alkalinity are used for every 1 ppm of ammonia. The enzyme in Nitrosomonas that carries out the first part of ammonia oxidation is inhibited (rendered inactive) by pH less than 7."

From 4 Ammonia in Wastewater Treatment

By aged, I meant water that is sit out from the tap. But that really depends. Essentially if the taps in your system are not exposed to any air (which includes CO2) when it gets exposed to CO2 in our atmosphere it will acidify.

It is true aeration also reduces CO2, that is because you are causing bubbles. CO2 does not dissolve in water very well, the more surface tension or bubbles you produce the CO2 will be more than happy to leave than to stay in the tank. Thats why also people tend to reduce surface tension when they have planted tanks.

If you are considering "aged" water as used aquarium water, that is also true about bacteria, but it is not the only source. The reaction has to release protons, you are going from ammonia NH3 to NO2- and then NO3-, the Hs have to go somewhere! And bingo it is INHIBITED lower than ph, just because of that reaction.

I'm saving my time so look here
Nitrification - Wikipedia, the free encyclopedia

If you think about all my talk about balance, just look at the first equation. If your pH is lower than 7, there are more protons. The protons are on the right side. What does nature do, it makes the reaction go in reverse, essentially stopping the conversion from ammonia to nitrites.

[punchbuggy]

"So what am I advocating? Nothing. I just needed to do this to clear the air. But I am not pushing any specific KH/GH value. Why? Because different species require different conditions. What I do know is that NOTHING can survive in pure water. There is too much variation from tank to tank to suggest anything (type of substrate for instance). The only thing I would suggest is that people not add tons of chemicals because of their test results. Things are ALWAYS in balance. The more you try to push it in one direction, the HARDER nature will push back to fix it. To finally “force” your condition in a system that does not want to be at that condition, would require so many chemicals your fish will die."

punchbuggy,
Thanks for the FAQ. I think all levels of hobbyists can appreciate what you have posted. I am not sure however how to interpret the above quote. Yes, I agree, things always tend to be in balance of some sort but we are maintaining closed systems here where we decide what parameters to run for our particular aquarium habitants. As you said, the fish can't jump out of the aquarium and find what is best for them. Maybe I am misreading the quote but my concern is for those who might read this last part and interpret it as add nothing you will be fine. If our water parameters in the wild were to change drastically, many fish would adjust to the conditions, many would also die. Our water source is closer to "pure water" then any water in Canada, as mentioned, not the best condition for aquarium fish. Before we were adding appropriate buffers at IPU we had many issues with certain species of fish, in particular livebearers and Goldfish. After adjusting the parameters we realized how these low levels were affecting the vast majority of the fish in our care. I found the relative comparisons, particularly the bath good examples. This is not a criticism, just looking out for the masses. Your example of thriving not surviving is the key here to making a change. Great reading.

I thin what I meant was

1) I'm not telling people to DO IT. That is there choice, if they like to waste money that is there perogative.

2) But that why I added that nothing can survive in pure water (hint hint)

3) I agree that some species don't do well, but I wanted to say instead of adjusting adjusting adjusting, people should make up their minds with the type of fish and then adjust appropriately, preferably during setup. Don't go from some hardwater species tank to a softwater one. Thats essentially the same as converting a marine tank to a freshwater one. It is unfair to the fish and to your own pocketbook to constantly adjust with more and more chemicals.

Cheers
Kelvin

[Rastapus]

I thin what I meant was

1) I'm not telling people to DO IT. That is there choice, if they like to waste money that is there perogative.

2) But that why I added that nothing can survive in pure water (hint hint)

3) I agree that some species don't do well, but I wanted to say instead of adjusting adjusting adjusting, people should make up their minds with the type of fish and then adjust appropriately, preferably during setup. Don't go from some hardwater species tank to a softwater one. Thats essentially the same as converting a marine tank to a freshwater one. It is unfair to the fish and to your own pocketbook to constantly adjust with more and more chemicals.

Cheers
Kelvin

Kelvin,
Now I am confused. How are hobbyists wasting money by buffering their water? The two statements are contradictory, fish don't live in pure water but adding chemicals is a waste of money. Please help me understand where you are going here.
Yes fish will adapt to low hardness to a point, we have 0 hardness, a condition which is rare in any other city and unheard of at fish farms where most of our fish come from. Fish coming out of a hardness of 10 break down in a hardness of 0. It is too drastic a change for most. Softwater fish can adapt yes but we have seen a marked improvement in all fish health since making these changes. It has also been an up hill battle to convince other hobbyists of this so naturally I am concerned in a few comments that will derail the efforts. I would not be adding more chemistry to the way hobbyists do things for any other reason then to ensure success. Our business relies on the success of our clients, not the sales of buffer. Fish will not get prunish like we do as per your example, many will either get sick or die. We have seen the drastic results of both sides, I would much rather have our clients on the positive side. Your explanation of "balance" explains both the necessity of it and the inevitability of it. However without proper mineral content, unadjusted BC water will result in more failed aquariums and more failure in hobbyists.

[Rastapus]

"The more you try to push it in one direction, the HARDER nature will push back to fix it. To finally “force” your condition in a system that does not want to be at that condition, would require so many chemicals your fish will die."

Kelvin,
Again, just looking for healthy debate here but also to clear up some confusion I am having. If an aquarium is left unbuffered with no influence by the hobbyist, the pH will gradually drift to an acidic environment, destroy the biological filter and fish will die. The above statement baffles me, our water source is the problem. If we had water from a stream as in nature it would be properly buffered for fish that we would keep from that river. We as hobbyists are keeping fish from different water requirements not met by our water source. By "forcing" the condition to correct for what is lacking, how can that be interpreted as a system that does not want to be in that condition?
In nature, changes tend to happen over time and creatures evolve to meet the condition. How many species have been wiped from the earth due to changing condition? By rationale, don't buffer and let "nature" in a closed system run it's course? The result will be a lot of dead fish.....

[Mferko]

fantastic post!

btw grant i dont think he meant they are wasting my money by buffering their water
what i got out of that was: keep things stable
research the conditions your fish like, set your tank up accordingly and dont constantly adjust, keep it stable
nothing survives in pure water so not buffering and having your fish die is the waste of money, be a fish keeper not just a fish buyer.


to the OP: can you please touch on equilibrium in regards to gas exchange, can injecting CO2 make fish have a tougher time exchanging their excess CO2 with the environment? seems to me it would...