kh tester

[john1]

Hi there

I've got in my collection a few testers (chemical). They all seem straight forward except the "Aquarium Parmaceutical GH & KH tester"

The instruction tells you after 1 drop it goes to blue. When it is bright yellow the test is finished. WHAT is the definition of 'bright'?

I filled 4 test tubes with 1 drop increment and they are ALL yellow.

Please explain

Thanks John1

[Pegasus]

Hi John1. Glad you could join us. We have a few members from your side of the water (See members list)

Bright Yellow.... They don't make it easy do they.

Suppose bright yellow is a "pale" yellow, or a "washed out" yellow... like a...... banana perhaps, but slightly paler.

Did you not get a colour chart with your testers ??

I have a meter that reads my pH as I can never really determine what true shade the colour should be, even with the colour chart.

We have a few clued up members here, so perhaps they might be able to explain a little better.

What sort of fish do you keep??

Regards,

Bill (Pegasus)

[Caryl]

I had the same trouble as you John and, like Pegasus, I have yet to have a test match the colours on any chart!

Those pH meters are supposed to be good. Do you like yours Pegasus? How long have you had it?

[Caryl]

PS. The smileys are what I would call bright yellow

The hair on my angel is bright yellow.

[Pegasus]

The question is "when does YELLOW become LEMON" or visa versa

Errmmm.... pH meter....

My son got me it with the tank he so kindly provided me with.

I bought a test kit for pH, but the blasted thing only goes from 7.4 to 8.8

I ask you, what damn use is that if you need acid conditions, and it was $10:70 at that.

The pH test strips were the most acurate thing I have used. You COULD get them at the chemist, but I don't know if you still can, but they gave a definite colour that you could match to a chart.

Accuracy.... Can't really say, as I have nothing to compare it to that can give me a correct visual reading, but the water TASTES and SMELLS pretty normal and that's usually a good indication for me. he he.

Bill.

[Midas]

I haven't used the Aquarium Parmaceutical GH and KH test kit but I do use the Hagen version. It sounds like Hagen uses the same chemical colour system as they also start at blue and go yellow. If your water sample goes yellow after 1 drop (assuming the kit is working properly, which it probably is) then your KH will be less than the smallest reading of the kit. The hagen kit says to mulitply the number of drops added by 10 to get the KH in ppm. So if after 1 drop it is already yellow then the KH will be less than 10.

If you want to see the point where it goes from blue to yellow add a small pinch of baking soda to the water sample that you test and this should increase the KH to a measurable level.

Also if your KH in your tank is less than 10ppm your tank pH is probably already quite low or is heading for a pH crash so you might want to gradually add some sodium bicarbonate (baking soda) to your water to buffer it a bit better to help keep the pH up (if you want to keep it up that is)

[john1]

Hi Midas

Thanks for the info. You mention 10. I presume you mean 10 deg. dKH. According to my infosheet by Aquarium Pharmaceuticals it should be 3 to 6 for most tropical fish. I think I figured it out. I filled 5 vials with the auarium water and added each in 1 drop increments. Then I stared at 5 vials. 4 were almost the same. The fifth was much darker (brighter?).

So therefore the water has a hardness of 5 deg. or 89.5 ppm. I really don't know what value it should be in a community tank. Any suggestions?

John

[Rob]

There are different units used to measure KH. ppm = parts per million is one of them, another is dKH. From memory 10ppm = 1 dKH.

Just went and checked, 10ppm = 2.8 dKH (according to Aquarium online australia)

[Pegasus]

Hi John,

I'm a little confused here, as I didn't know you could colour test for hardness :oops:

When you mentioned "bright yellow" in your original post I thought we were talking pH.

For your water to have 89.5ppm of hardness I would think your tester DOES show bright yellow, and so your water must be quite soft and slightly acid.

As far as I know, you can't have hard acid water, nor can you have soft alkaline water, so the hardness is related to the pH.

I'm not up to date with todays testers, not at the prices they ask for them, but we used to test for hardness with a soap solution, eg, so many drops to lather.

Hi Rob, We must have posted at the same time. he he.

Whats the "K" and the "G' stand for... perhaps kelvin (heat.. more confused) ?? and General???

As I said, I'm a little behind the times here :oops:

Bill

[Warren]

Midas means 10ppm which is not quite 1dH (1dH=approx 15.5ppm).

If you look down through the test tube with white paper behind it, the colour is a lot stronger. The KH & GH test kits are meant to be used this way. Also it is not the intensisty of the colour you are looking for it is the colour change.

The indicator changes colour to tell you you've reached the point where all the KH or GH is used up and therefore reflects how much there was in the sample.

If you continue to add the titration solution once the colour has changed the colour will get stronger but this only wastes the test kit. As previously said, it is the colour change, not the colour intensity that matters.

If one drop is all it takes to change the colour, you have less than 1dH of KH. I'd expect you also have a pH of 6.0 or less. With a KH this low, you could have a lot of trouble with pH crashes. Adding some baking soda (sodium bicarbonate) will increase the KH and add some pH buffering. Approx 1 teaspoon per 1000L will increase KH by 1dH. Add the baking soda to 2-4 Litres of water. Set a very thin siphon tube to slowly add the dissolved baking soda to your tank in a high flow area. It needs to be introducted very slowly (30 minutes or longer) as the baking soda can react with acids in the water to produce CO2. If it is added too quickly the CO2 level can rise and be dangerous for the fish. Adding it slowly allows the CO2 generated (if any) to dissipate. Also the blood salt levels in the fish need time to adjust so they do not suffer from osmotic shock through their gills. You will know if it is being added too fast as all or some of the fish will gasp at the surface.

[Rob]

There are two types of hardness - general hardness (which is a measure of the amount of calcium and magnesium ions that are dissolved in the water). The second type of hardness is carbonate hardness, the amount of carbonate dissolved in the water (I think the differentiate between the two for a couple of reasons - carbonates influences pH, where Mg and Ca don't; also carbonate hardness can be removed by boiling the water).

So GH = general hardness

KH = carbonate hardness (only thing is the Germans thought up these scales and they spell carbonate with a K).

You may also come across both of these with a 'D' infront of them, usually the d isn't an abbreviated degrees but rather an abbreviated deutsch (ie german).

ps. baking soda is Sodium bicarbonate - hence it's effect on carbonate hardness (and also pH).

[Warren]

Oops, I meant sodium bicarbonate, - thanks for picking that up Rob!!!!!

Have edited the previous post to correct.

[Ira]

Ira what's? :-? I didn't think I'd posted anything in this thread. That's the second time in 2 days someone seems to have confused me with someone else, last time was Caryl. Unless there's another Ira?

[Warren]

I must be related to Britney!!

Sorry Ira, don't know where that came from, should have been 'Midas'. Have edited the post (again) to correct. Must be having a blond day!

[Pegasus]

Thanks for that info Rob. In the early days the only hardness we were concerned with was the dH I believe, which is also a German conception I believe.

When things start getting TOOOOO technical I revert to old memories, which always seemed to work

Thanks,

Bill.

[Caryl]

Britney is no more blonde than you are Warren!

Have I confused you with someone else Ira or has someone else confused you for me? Sorry about that!!

Thanks for the explanation Rob, I always wondered about the d.

[Ira]

In the technical forum, the aquaclear filters thread. You said, "I now wonder if the ones Ira meant are different too. " Maybe I did say something about aquaclears, but I can't remember or find it. I must be getting really popular, hehehe.

[Caryl]

Either that or we think you need more help than others :lol:

I actually think it was Fatman who originally asked about AquaClears.

[Derek]

Does anyone "know" what if any compounds may interfere with the results from this type of KH test.

I am unfamiliar with the chemistry of these tests but do phosphates or tannic acids from wood or peat, for example, interfere. If so do they tend to gve an artificiallly high or low reading and is there any way to correct for it.

[john1]

Bill, you are right with too technical. Unfortunately if you don't keep up you'll be left behind. Not that your fish or plants will suddely die, but if there was something wrong in your tank, in the olden not too technical days, you did not know what. Lack of info, lack of tests. Yes you are right, 30 years ago one only mentioned dH. Degrees hardness what, general or carbonate? . It only seemed to make everything easier. Actually it was harder. If fish died and your pH, dH, and temperature was ok, then all you could do was scratch your head. Nitrate, nitrite, sodium, ammonia, co2 etc. was only known to the industrial chemist. Now with all those tests available to us it is much easier to stop a possible 'death' epidemic breaking out in your tank. Naturally it is also damn expensive.

John

[Pegasus]

Hi John,

Well, up to now you've been a good boy, but I don't agree with all you say. We knew about ammonia/ammonium/nitrite/nitrate/hardness/pH/water chemistry, which saw us through the hobby, but as you say, things change, and you have to keep up with developments, but you say,

but if there was something wrong in your tank, in the olden not too technical days, you did not know what.

Perhaps we didn't have ALL the answers, but if I in particular had a prob I found out why, after all it was my living for almost twenty years until I shut shop.

We didn't have ALL the answers because there wasn't ALL the questions and confusion there is today, in fact I am not surprised that many hobbyists leave so quickly after being faced with all the tech jargon that one supposedly has to know in order to keep fish.

If one or more of my fish died I would want to know the reason why, even if it meant cutting it open and examining it under a microscope.

Say what you want, but 80% or more of fish deaths in the hobby today are caused by negligence, not the lack of understanding the latest technology, but the understanding of the very simple basic rules of fishkeeping that are so easy to learn if more people cared to take the time.

Regards,

Bill.

[john1]

Rob

I think you err with both.

According to my literature 1dGH or kH = 17.9 p.p.m.

In case you are interested, here are some facts.

dGH = dKH + PH

GH = Total Hardness

KH = Carbonate Hardness

PH = Permanent Hardness

And you say I know nothing HE HE

John

[john1]

Bill

Either I expressed myself wrongly or you misunderstood. By "in the olden days we didn't know much about nitrate, nitrite, ammonia etc", I did not mean you personally. What I really meant was the average hobbyist/aquarist.

Please do not take it personally. I really do respect your opinion.

Please forgive.

John

[Pegasus]

Hi John, you say,

Please do not take it personally. I really do respect your opinion.

Please forgive.

Nothing to forgive my friend. The forums are here to express our thoughts and opinions.

There were a few of us that hopefully made a contribution to the hobby of the early days by passing our knowledge along and where possible breeding true to type, and I would like to class myself as one of those people.

Happy Days

Regards,

Bill.

[cees]

Does anyone "know" what if any compounds may interfere with the results from this type of KH test.

I am unfamiliar with the chemistry of these tests but do phosphates or tannic acids from wood or peat, for example, interfere. If so do they tend to gve an artificiallly high or low reading and is there any way to correct for it.

Hi Derek,

Don't know what type of test one is talking about. Is it a 'titration' or a colour comparison?

In any case, fwiw

Carbonate hardness is defined as that portion of all calcium ions (Ca2+) and magnesium ions (Mg2+) present in 1 liter of water for which there exists an equivalent amount of hydrogen carbonate ions (HCO3 -) and carbonate ions (CO3 2-) originating from dissolved carbonic acid. (sorry, forum doesn't allow sub and super script)

The so-called "German degree" is frequently used as a practical measurement unit for hardness; this degree is defined as follows:

1°d = 10 mg/l CaO

(and that is 10 ppm CaO or 17.9 ppm CaCO3, or zillion ppm sheep)

The methods to determine carbonate hardness rely on the acid consuming character of carbonate/bicarbonate. It's either a titration (obvious colour change, count the drops (or use a buret if you want to get technical). Or the test measures the resulting pH after addition of a fixed amount acid. Usually done by colour comparison of some sort.

Strong bases or other acid consuming substances such as phosphates and polyphosphates interfere with most (if not all) carbonate hardness test. And that would result in an artificially high value.