What's In Your Water?

[The-Wolf]

Water. H2O. A colourless, tasteless and odourless substance without which there would be no life on this planet. In an aquarium there are many things that make up the aquatic environment.

Ammonia. NH3. A colourless, toxic gas with an irritating, tear-producing odour.
Too much ammonia will have severe consequences on all aquatic life. Readings should be 0ppm at all times.

Some ways to remove ammonia.
Add activated carbon or zeolite to your filter, perform a water change or add a commercially available ammonia remover.

Nitrates. HNO3. Concentrations above 150ppm may be hazardous.

Some ways to remove nitrates.
Perform a water change, add a commercially available nitrate remover.
Note; Juwel now do a nitrate removal sponge, for their systems.

Nitrites. HNO2. Extremely toxic to most aquatic life. As little as 0.2ppm is harmful to most fish.

Some ways to remove nitrites.
Perform a water change, add a commercially available nitrite remover.

pH. This is an extent of the acidity of water. The scale is pH0 (very acidic) to pH14 (very alkaline) pH7 is neutral.

Some ways to lower pH.
Filtering water over peat, Adding bogwood to the tank (both have a limited effect),
Inject carbon dioxide (CO²), perform water changes with RO (Reverse Osmosis) water or use a commercially available acid buffer.

Some ways to raise pH.
Aerate the water, driving off the carbon dioxide (CO²), add crushed coral or seashells to the filter, Add rocks containing limestone, use a coral sand substrate or use a commercially available alkaline buffer.

KH. This is an extent of the, temporary, hardness of water. This is derived mainly from carbonate and bicarbonate ions and directly reflects the buffering capacity of the water. It can be removed by boiling the water. (This is why lime-scale builds up on heater elements.)

Some ways to raise KH.
Aerate the water, driving off the carbon dioxide (CO²).
add a commercially available product to increase buffering capacity.
add NaHCO3 (baking soda)
Note; 5ml (1 teaspoon) of baking soda added to 50 litres of water can raise the kH by approx 4 OdH without effecting the pH greatly.

Some ways to lower KH
Injecting carbon dioxide (CO²). Note has limited effect
Add a commercially available product to decrease the buffering capacity
Perform water changes with RO (Reverse Osmosis) water.
Note: You can mix tap water with reverse osmosis water to attain the desired kH level.

GH. This is an extent of the hardness of water. This is derived mainly from the concentration of magnesium and calcium ions. (Other ions can add to water hardness but are usually irrelevant and not easy to measure.)
Note; It is GH, not KH that is being referred to when talking about fish that prefer soft or hard water. GH will not directly affect pH although "hard" water is generally alkaline due to some interaction of GH and KH.

0 to 4 OdH or 0 to 70 ppm = very soft
4 to 8 OdH or 70 to 140 ppm = soft
8 to 12 OdH or 140 to 210 ppm = medium hard
12 to 18 OdH or 210 to 320 ppm = fairly hard
18 to 30 OdH or 320 to 530 ppm = hard
Anything above this is very hard
OdH = German degrees hardness (the standard measurement), which is equal to 17.9 mg/L or ppm.

GH & KH range for aquatic life
0°-3° (0-50 ppm)..........................discus, arowanas, elephantnoses, neon & cardinal tetras and live plants.
3°-6° (50-100 ppm).............most tropical fish including angelfish, cichlids, most tetras, botias and live plants.
6°-11° (100-200 ppm)..................most tropical fish including swordtails, guppies, mollies and goldfish.
11°-22° (200-400 ppm)...............Rift lake cichlids, goldfish and brackish water fish.

Some ways to raise GH
Adding limestone to the aquarium (this will also increase KH which in turn will increase pH)
Adding CaCO3 (calcium carbonate) will raise GH and KH

Some ways to lower GH
Use a commercially available water softening product.
Mix tap water with reverse osmosis (RO) water.

Phosphate PO4-.
Phosphates can cause an algae bloom and consequently an oxygen deficient environment for aquatic life.

Some ways of removing phosphates.
Perform a water change or add a commercially available phosphate removal product to your filter.

Iron. Fe
Iron is one of the many nutrients that plants need. Low levels of iron effect the growth and health of plants however high levels of iron is very harmful to fish.

The safe levels of iron are anything under 1ppm

Some ways of increasing iron
add a comercially available plant food or fertaliser

Some ways of lowering iron
perform a partial water change(s) preferably with RO water.

Oxygen; O2
O2 is essential for most aquatic life.
A safe level of O2 would be at 4ppm

Some ways of decreasing O2
Inject CO2 via a commercialy available kit.
turn off airstomes
reduce or eliminate surface movement

Some ways of increasing O2
ensure good surface agitation
turn off CO2 injectors

Carbon Dioxide; CO2
CO2 is essential to plant life, just as O2 is to us.

The safe range of CO2 is between 10 and 40 ppm

Some ways to decrease CO2
reduce CO2 injecters
create a good surface agitation

Some ways to increase CO2
turn up injectors
turn off airstones

Copper; Cu
Copper is very toxic to fish, invertibrates and microorganisums.

The safe level of Cu is 0.3ppm

some ways to decrease Cu
perform a large water change
add activated carbon to the filtration system.

Chlorine/Chloramine; Cl/Cl2
Chlorine is a very toxic gas and is used by water suppliers as a dissenfectant.
Chloramine is a liqued and many water suppliers are now using this instead of chlorine as it is just as effective and eaisier(safer) to use.
Both are very toxic to aquatic life.

the safe levels of Cl/Cl2 are Zero

Some ways of reducing Cl/Cl2
treat with a commercially available water conditioner.

Note;
Cl will naturally dissipate from water over a period of time as it revers to its gassious state, however
Cl2 will not and must be delt with as above. As it is almost impossible to know which treatment your water supplier has used (unless you ask them) it is good pratice to assume they have used Cl2.


I HTH someone.
credit must go to skimpy for the gH & kH range for aquatic life & clutterydrawer for pointing out I'd missed how to remove nitrite, nitrates and ammonia. (now Added )
Thanks to gf225 for pointing out minor errors.

 

[enchanted]

This should be a sticky!

Excellent information.

 

[clutterydrawer]

Excellent

You could add info on how to lower ammonia and nitrite readings(...water changes) for anyone whose tank is experiencing high readings of them.

 

[skimpy]

Very clear, great post - i agree this should be pinned - Hey Mods how about it!

EDIT : On the same subject Wolf - this below might be interesting to add, a lot of people are unaware (like me when I got my fish) that these guide lines exist.

I chose to have livebearers but my tap water is more suitable to discus, arowanas etc. Perhaps if I had know before I would have looked at different fish etc.

GH & KH RANGE_________AQUARIUM LIFE

0°-3° (0-50 ppm)..........................discus, arowanas, elephantnose, neons, cardinals, live plants

3°-6° (50-100 ppm).............most tropical fish including angelfish, cichlids, tetras, botia, live plants

6°-11° (100-200 ppm)..................most tropical fish including swordtails, guppies, mollies, goldfish

11°-22° (200-400 ppm)...............Rift lake cichlids, goldfish, brackish water fish 

 

[The-Wolf]

Thanks CD and Skimpy, changes have now been made

 

[skimpy]

Anyone else. Come on everyone. This is a really great post and I think it would be very helpful if it was pinned.

Anyone who agree's please post to say so, Wolf has gone to a lot of effort just to help us all, lets support him and let the Mods hear what we think so that they do consider pinning it.

edit - It need to be uptop, not disappearing lower and lower until no more.

 

[skimpy]

Hi Wolf,

Found some more information that might be helpful to your post, this is taken from this site. Water temperature and PH readings can make a big difference to the danger levels of ammonia.

Ammonia Readings

If your levels approach or exceed the levels shown, take emergency action IMMEDIATELY.

       Water Temperature
  pH       20C (68F)     25C (77F)
  _________________________________
  6.5        15.4                   11.1
  7.0          5.0                     3.6
  7.5          1.6                     1.2
  8.0          0.5                     0.4
  8.5          0.2                     0.1

Another interesting fact, although this can start to get complicated especially for beginners.

I work with someone who I did a water test for and her tank had an ammonia reading of 8.0ppm+ and a PH level of below 6.0 still her fish were ok. I therefore needed to investigate further to understand for myself. It appears that when ammonia is mixed with a low acidic PH it become ammonium, which is not toxic to fish in the same was as ammonia.

The main problem with this is to put her tank right, meant water changes, and water changes would raise her PH levels back to normal and reduce her ammonia levels. But when the PH reaches 7.0 the ammonium turns back to ammonia and becomes toxic again. Where the cross over point happens would be vitally important for her fish. Therefore the above chart came in very handy because we had to watch levels very closely. Luckly for her she has cold water fish so she had a larger margin than some of us would have had.

You may not want to use this in your post, but I hope you find it interesting anyway

 

[Angry_Platy]

I hope a mod pins this....this is excellent information....

Thanks to TheWolf (who I still refer to as danio)....

 

[sunflower]

Dont forget, nitrates should ideally be below 40ppm and Nitrites should always be at 0.

 

[skimpy]

Hi Wolf,

Its me again I think this is too good a post for it to just drop down and dissappear, so I've brought it back up again. Is there any chance this could be pinned, I think it is sooooooooo helpful to what is a very complicated subject, especially for a beginner it does put it into simple easy read terms. So many of the dreaded illnesses that fish get could be decreased if we all had a better understanding of water chemistry.

TFF is a great forum and really there to help people, and this is really helpful

 

[Def]

Yep, vote for a pin here.

 

[Bignose]

I agree the post is a nice and concise way to introduce all to the complicated water chemistry that we keep our fish in.

But, I think one important thing is missing from the "removal of ammonia and nitrite sections" and that is simply that a fully cycled tank should not have these anyway! A beginner might take a post like this as the only way to remove ammonia etc is through water changes or *shudder* constantly adding chemicals to the water. I would suggest that you denote two categories. 1st would be "Nature's" or "The long-term" way of removing ammonia, nitrite -- the bacteria should grow to consume it. Then, secondly, denote an "Emergency" way of removing ammonia, the activated carbon, chemicals, water change, etc.

Also, maybe I am being a stickler, but all those chemistry classes should be worth something, so here goes:

The ammonia-ammonium is always in equilibrium

NH3 + H2O  <-->  NH4(+) + OH(-)       (let's call this reaction A)

The left hand side is ammonia (no charge) + water (no charge) is in equilibrium with, on the right hand side, ammonium (+1 charge) with OH (-1 charge). The numbers are all supposed to be subscripts, but we can work with what we got on the message board.

This eqiulibrium is, well for lack of a better word, in equilibrium with several other reversible reactions.

Water itself:

H2O  <-->  H(+) + OH(-)   (reaction B)

And, any acid (which I will just call R. R can be phosphoric, or sulfuric or anything)

HR <--> H(+) + R(-)   (reaction C)

This can be more complicated, since some acids can give up more than one H(+), but for this general discussion the above is fine.

Finally, a more explicit definition of pH is needed:
pH really means the negative of the base-10 logarithm of the concentration of H(+)

for example: if the concentration of H(+) is 10^-8

-log_10 (10^-8) = -(-8) = 8

So, at low pH, there is a higher concentration of H(+)'s, (named acidic)
for example, pH of 5 means the concentration of H(+) is

10^-5  >  10^-8

above.

So, here is the equilibrium...

If the water is more acidic, the amount of H(+) is high from (C ). In order to try to maintain a charge balance, the water disassociates via reaction (B ). Then the extra H(+)'s from that find the ammonia and forms NH4(+) reaction (A). Which, as mentioned above, ammonium NH4(+) is less toxic. Therefore, we see that at lower pHs, the equilibrium is shifted towards the less toxic ammonium. And, at the higher, more basic pHs, the eqiulibrium is shifted toward bare ammonia, more toxic to fish.

So, this explains the chart listed above -- not so much by just "mixing ammonia with low pH" but by explaining that the ammonia-ammonium and pH are all very interconnected.

Edit: put the equations and reactions in code boxes so they printed right (without smilies)

 

[Def]

In future, I'm just going to PM Bignose all my questions as he's clearly Einstein in disguise.

 

[Puffer_freak]

Although I haven't read all the way through it ( )) I am sure that I will soon feel the need to read it! This would be easier if it were pinned! Also, if it gets pinned, take off all the unnecesarry stuff, and just add all the suggested info to the original post!

 

[purple_drazi]

I just found this thread and I think it should be pinned. Lots of basic info that us newbies don't quite have a handle on yet!