Ok, Heres A Bit Of A Mad One!

[monkeyman]

Ive just tested the pH of my COLD tap water and it sits at 6.0. Then i tested the pH of my HOT tap water and it is 7.0. Has anyone else ever tested hot & cold tap water??? What the heck is going on??? ANYONE FANCY DOING A TEST AND PUTTING THE RESULTS ON HERE???

 

[demonmagus]

I think the hot tap water comes through different pipes, but I don't know tbh

 

[timmystood]

Sure - i'll do one now... give me 10 minutes


Just done - Cold 7 & Hot is about 8.5 (hard to read scale!)

 

[monkeyman]

Sure - i'll do one now... give me 10 minutes


Just done - Cold 7 & Hot is about 8.5 (hard to read scale!)

Good stuff! Thanks for your SPEEDY help! That is mad eh? Hope some others post results & maybe some one can shed a bit of light on it!!!

 

[a.d.wood]

Hi there,

pH is affected by temperature, the hotter the water the higher the pH reading. A lot of laboratory grade pH probes have built in temperature compensation (but even this only operates reliably within a small temperature range).

Leave your hot tap water to cool (and the cold to warm up) and you should get similar readings.

Under normal circumstances it is best to test pH at 'ambient' temperature, which is normally taken to be around 20 degrees C.

Your little experiment also highlights the fact that you should always try to measure the pH at the same temperature to make sure you are making a proper comparison.

Andrew

 

[monkeyman]

Ok! Sounds good to me... Now i have a major problem & saying as you know about pH im hoping you can help. I have a jewul vision 260 tank for the past 3 years fully cycled and all that jazz... I recently tested my water and it was reading 5.0. I know this is because i recently added bogwood (for decorational purposes) which i now know lowers the pH. It was in there for about a week. So... wayyyy to low, so i took out my bogwood and done a 70% water change (not recommended i know, but i wondered why my rainbow shark had died). Almost every night for a week after i done a 30% change and juring the past 2 weeks i have jus done a weekly 20% change. Now i tested my water tonight again from my tank and it was still reading 5.0%. This is doing my head in. Someone please help! i wood love my pH to sit around 7.0, but have decided against chemicals.

 

[monkeyman]

Does anyone know???

 

[Torrean]

Umm I'm sorry what's your question?

Look at the pinned topics in chit chat. They should help you out with any PH problems your having,

 

[Dorkhedeos]

hotwater has to go through your water heater first

 

[a.d.wood]

Umm I'm sorry what's your question?

hotwater has to go through your water heater first

Thanks for this input > it really helps NOT

Hi there,

Given your tap water is sitting at around pH 6, then achieving pH 7 in the tank can't be achieved unless you add something to bring the pH up.

Why do you want to get pH 7, most of your common fish will tolerate a fairly wide pH range and I think you will find the best thing you can do is leave the pH alone (a stable set of water stats are much better for your fish rather than constantly adding buffers and chemicals to alter the pH).

As your pH is still reading 5 in the tank, do you have any bog wood, peat etc left in there otherwise I would grab a new test kit

Andrew

 

[monkeyman]

Umm I'm sorry what's your question?

hotwater has to go through your water heater first

Thanks for this input > it really helps NOT

Hi there,

Given your tap water is sitting at around pH 6, then achieving pH 7 in the tank can't be achieved unless you add something to bring the pH up.

Why do you want to get pH 7, most of your common fish will tolerate a fairly wide pH range and I think you will find the best thing you can do is leave the pH alone (a stable set of water stats are much better for your fish rather than constantly adding buffers and chemicals to alter the pH).

As your pH is still reading 5 in the tank, do you have any bog wood, peat etc left in there otherwise I would grab a new test kit

Andrew

Thanks very much A.D.! Someone chatting sense at last! I bought a new test kit yesterday, a good tetra kit one it was £6.00! It says it is 5.0 same as my old test did. So im thinking thats definately wat it is... NOw, there is nothing left in the tank to make the pH stay so low, like you say bogwood or the like. I know the pH of 5.0 isnt such a problem because all my fish are fine, healthy eating well , full of coulour etc etc...

It only bothers me so much when i add new fish! I got a new 4" oscar yesterday and the water he came in was at 6.5pH (i tested it out of the bag) and i know that that jump isnt good 6.5-5.0! Anyways, its really doing my head in but im just going to keep changing my water and hope that helps a bit...

If i could just get it back to 7.0 or there abouts like it was before i put that damn bogwood in! Thanks again for your help bud

 

[Bignose]

Three notes, first you should always let your tap water sit out for several hours (overnight) so that any dissolved gases in your tap can leave, and you get a reading of what the long-term pH of your tap is. Dissolved carbon dioxide is the usual suspect here, and having extra CO2 in your tap water (which is not uncommon) will artificially depress your pH at the moment it comes out of the tap.

Secondly, pH is dependent upon temperature, in a lot of ways exactly what was in the first note. Warmed liquids dissolve less gas in them, less CO2 dissolved in the water leads to a higher pH.

Thirdly, what you really need to know in this case is a measure of your KH, which stands for carbonate hardness. This will let you know how much buffering capabiity your water has. If you don't know buffering is the ability of your water to keep the same pH. It is also called akalinity (or acidity). Since your water went down so much just from adding a piece of wood, I would suspect that you have a pretty low KH. This means that your pH may fluctuate quickly, which is really unhealthy for your fish -- it is stressful to have to keep adjusting to changing pHs. If you don't have a KH test, but a GH (general hardness) test, thay would be ok, though its information is more indirect that a KH test. If you don't have either and don't want to buy them, please take a water sample to your LFS, most will test it for free for you.

Finally, this was said above, but I'd like to reinforce it, that is that your fish will adjust to what you or your favorite book/website may call "sup-optimal" pH for your fish. However, if you keep the pH steady at almost any value between 5 and 8.5, most fish will live perfectly happy live. Steady is the key word here. There are a few sensitive species, discus are the first example that come to mind, this is where lots and lots of research before you buy comes in.

To wit, my water is hard and alkaline, with a pH between 8.2 and 8.4. I have kept and bred tiger barbs, lemon tetras, and bronze corys. I have also kept blue gouramis, scissortail rasboras, mollies, siamese algae eaters, and peppered corys without any health problems at all. With the exception of the mollies, a pH of 8.2 was outside the range of all these fishs' range in multiple books and websites, but they all seemed pretty satisfied to me. Especially if they are mating, they must be reasonably happy.

So, once again, keeping a constant pH is far, far, far more important that keeping an exact pH.

 

[monkeyman]

Thank you so so much guys, your help and advice is greatly appreciated on here... So glad i can come on here and get good solid advice!

 

[Littlelady]

Three notes, first you should always let your tap water sit out for several hours (overnight) so that any dissolved gases in your tap can leave, and you get a reading of what the long-term pH of your tap is. Dissolved carbon dioxide is the usual suspect here, and having extra CO2 in your tap water (which is not uncommon) will artificially depress your pH at the moment it comes out of the tap.

Secondly, pH is dependent upon temperature, in a lot of ways exactly what was in the first note. Warmed liquids dissolve less gas in them, less CO2 dissolved in the water leads to a higher pH.

Thirdly, what you really need to know in this case is a measure of your KH, which stands for carbonate hardness. This will let you know how much buffering capabiity your water has. If you don't know buffering is the ability of your water to keep the same pH. It is also called akalinity (or acidity). Since your water went down so much just from adding a piece of wood, I would suspect that you have a pretty low KH. This means that your pH may fluctuate quickly, which is really unhealthy for your fish -- it is stressful to have to keep adjusting to changing pHs. If you don't have a KH test, but a GH (general hardness) test, thay would be ok, though its information is more indirect that a KH test. If you don't have either and don't want to buy them, please take a water sample to your LFS, most will test it for free for you.

Finally, this was said above, but I'd like to reinforce it, that is that your fish will adjust to what you or your favorite book/website may call "sup-optimal" pH for your fish. However, if you keep the pH steady at almost any value between 5 and 8.5, most fish will live perfectly happy live. Steady is the key word here. There are a few sensitive species, discus are the first example that come to mind, this is where lots and lots of research before you buy comes in.

To wit, my water is hard and alkaline, with a pH between 8.2 and 8.4. I have kept and bred tiger barbs, lemon tetras, and bronze corys. I have also kept blue gouramis, scissortail rasboras, mollies, siamese algae eaters, and peppered corys without any health problems at all. With the exception of the mollies, a pH of 8.2 was outside the range of all these fishs' range in multiple books and websites, but they all seemed pretty satisfied to me. Especially if they are mating, they must be reasonably happy.

So, once again, keeping a constant pH is far, far, far more important that keeping an exact pH.

That was very informative and really helped me to understand more about that aspect of the water chemistry thank you very much