question about KH/GH in relation to TDS [Archive]

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sublevel007

11-27-2006, 04:03 PM

I was reading another thread on here and they started talking about the relation between KH/GH to TDS. Does anyone know the formula you can use from your GH and KH to come up with your TDS. I used to have a probe to check this but the guy I lent it to moved. I told him to keep it and i would get another but as you can see I'm pretty lazy, thanks for the responses guys!

fishmama

11-27-2006, 04:47 PM

Yes-

I am curious about that as well because mine don't seem to "add up"...
KH 100ppm
GH 20ppm
TDS (per Hanna meter) 325

Can someone tell me how that works?

Thanks,
Lisa

Graham

11-27-2006, 06:06 PM

The numbers do not have to add up...Remember that TDS is exactly that.......... everything that was once solid and is now dissolved........That can be anything from metals to minerals to Organic Carbons.

KH is just bicarbonates at our pH's and carbonates at much higher pH's. GH is mainly a test for Calcium and Magnesium while it can be composed of some other minerals. This is only one part of the TDS reading

Lisa the other 205ppm is anything and everything......In a lot of cases it's pollution.... DOC's and the water quality is down.

Test your water coming out of the tap, it'll be as clean as you can get

White Worm

11-27-2006, 06:12 PM

Yes-

I am curious about that as well because mine don't seem to "add up"...
KH 100ppm
GH 20ppm
TDS (per Hanna meter) 325

Can someone tell me how that works?

Thanks,
Lisa

What test did you use to come up with the KH / GH?

fishmama

11-27-2006, 07:03 PM

Graham

11-27-2006, 08:06 PM

If the GH measures "very soft", but KH is moderate, does that mean the "leftover" is lime, Na ion, etc?

ya lost me...Why would you think that the left over is lime,...calcium oxide:confused: or sodium/NA.

The left overs can be anyone of a number of different things, including organics such as carbohydrates, fats, amino acids, anything that forms organic carbons....DOC's

Our GH test kits measure calcium and magnesium and the KH test kit measures bicarbonates. The levels don't even have to be close to each other

annieb

11-27-2006, 08:09 PM

Yes-

I am curious about that as well because mine don't seem to "add up"...
KH 100ppm
GH 20ppm
TDS (per Hanna meter) 325

Can someone tell me how that works?

Thanks,
Lisa
Your GH of 20 PPM must be a typo, Lisa. KH and GH usually run very close to each other. A good rule of thumb if you're using a meter is to divide the PPM reading in half.

White Worm

11-27-2006, 08:16 PM

Hi Guys-

Thanks for the input. The KH/GH tests about the same whether I use my "quick dip" strip or API liquid drop test.

The TDS 325 is from the tap! It stays about the same in the tank because of frequent water changes. BTW-my water runs thru a household water softener, but on the lowest possible setting i.e. the resin beads do not regenerate very often thus more of the Ca and Mg are left in the tap water. I also tested a source from outside the house (it does not run thru the softener) and it measures about the same.

If the GH measures "very soft", but KH is moderate, does that mean the "leftover" is lime, Na ion, etc?

My fish are all doing fine, but I was just curious from a chemical point of view. I do not nor am I trying to breed any of my fish.

As Always,
Lisa
I think you need to look at them as seperate items. I think graham is saying that they dont correlate to each other as much as some would think. Each test measures different substances and your water is made up of many other things. You could check your local water report (usually online) to see exactly what is in your water. Once you do though, you may never drink it again or have your discus swimming around in it. I think that is also a good reason to have RO. How many drops until the color changes for KH? GH?

fishmama

11-27-2006, 08:30 PM

Yes...the GH 20 ppm is my reading per quick dip and api liquid test as well.

That's what I find odd...how can I have a really low GH and a much higher KH? I thought they correlated as well. I do have a website to our water report. I will find the link and put it in another post for any of those with water chemistry interests.

And I have read the reported avg info and it doesn't necessarily jive with mine. Bearing in mind the report is a year ago and that the data collected was probably many months before the report.

How would the Na ion from the water softener effect the tests results I am getting (or would it at all)?

Lisa

fishmama

11-27-2006, 08:36 PM

Our local water report link:

http://www.kcmo.org/water/ccr2005.pdf

Put on your reading glasses as the print is super small (or maybe I'm just getting old) ;-)

Lisa

Graham

11-27-2006, 08:37 PM

Your GH of 20 PPM must be a typo, Lisa. KH and GH usually run very close to each other. A good rule of thumb if you're using a meter is to divide the PPM reading in half.

Annie generally speaking they don't have a thing to do with each other............... Depending on what the water percolates through in the ground, to get to the water company, and then what the water company needs to add to your water for them to be happy, those numbers could be all over the place.

My well water comes out at about 60ppm KH and 40ppm GH, but the pH comes up to 7.5 from 6.5..........something else is buffering my water so with out spending $100 to have it analyzed I'll just live with it... I also have a lot of iron in my water..........think what a TDS meter would say

G

Graham

11-27-2006, 08:42 PM

How would the Na ion from the water softener effect the tests results I am getting (or would it at all)?

Lisa the Sodium would drive the TDS meter through the roof.....it's a dissolved solid....remember that anything that was once solid and is now dissolved will be read by the meter.......it would have no affect on KH and very little if anything on GH

fishmama

11-27-2006, 09:19 PM

Graham

11-27-2006, 11:56 PM

Lisa good question and I don't know the answer as I don't have a water softener. If it is a 1:1 ion exchange then it shouldn't up it at all

fishmama

11-28-2006, 12:16 AM

fishmama

11-28-2006, 12:19 AM

Hey Graham-

Thanks for clarifying TDS...for some reason I thought TDS was only dissolved inorganic compounds. I didn't realize is included organics.

Lisa

raglanroad

11-28-2006, 01:20 AM

Hi, maybe this might help
there is a slight addition to the explanations so far that I would like to add.
the TDS reading is really a calculation of the conductivity reading the meter is performing.
As mentioned, a reasonable "exchange rate" for making a guess for the relation of conductivity to TDS would be that if 50 ppm to 100ms. The two "readings" are really derived from information from testers which are the same, just that the TDS meter reads ms conductivity and calculates it for you into ppm TDS, whcih it isn't really...

This is because most river and lake water is similar, and we have river and lake water in the tap, so we can make such guesses.
If approximating an "exchange rate" to change ms into ppm, a closer rate would be 65 (phony ppm)"TDS" from 100 ms conductivity

different ions show different effect on the conductivity of water. some ions will not add much on the conductivity reading. You could have high ACTUAL TDS ( as opposed to the readings, which are conductivity related, not ACTUAL TDS) and low conductivity and "TDS" readings (phony TDS ), depending on which ions are in the water. If you have high conductivity, then you must hjave high TDS readings, and most likely do have high Actual TDS also, but not always as much as it could appear.

So we are really dealig with approximations and relying on common factors such as the similarities in ionic composition.of most normal rivers and lakes in ordr to make guesses.

raglanroad

11-28-2006, 01:43 AM

real TDS is related to what's left behind after all water is evaporated.
that's why it has no real direct relation to conductivity, since the different ions have different effects on conductivity... but we can pretend it does.

fishmama

11-28-2006, 09:52 AM

Thanks Raglan!

I learn something new every time I log in!

Lisa

korbi_doc

11-28-2006, 11:19 AM

It is my understanding that the "water softener" is an ion exchange resin...thus it only exchanges 1 to 1 ratio. The Na+ takes the place of either Ca+ or Mg+, and I would expect the TDS reading to remain the same. Is that correct?
Lisa

:) Lisa, I had a softener in NJ & well water (I'll miss it). Water thru a softener is good for an R/O membrane life...but, it raises TDS thru the roof due to the sodium ions....mine read 900+ppms...when I used it initially for discus, had problems, they did not do well, so had to go 100% R/O which was better cuz I avoided the nasty Atlantic City water problems...didn't mind the waste water cuz I didn't pay for water then..now I do, & the town water has a TDS of 85ppms, but the ph is high, comes in at 8.4 so guess I have to deal with that, lol.... Dottie ;)

annieb

11-28-2006, 02:13 PM

Hey Sublevel007-

Just noticed it looks like I stole your thread...hit a nerve I guess ;-)

Sorry! I don't know how to convert kh/gh to tds. But from reading the responses it looks like any "conversion" may be inaccurate.

Lisa

Hi Lisa.You are using a household water softener that is exchanging sodium for calcium and magnesium. That is the reason for your readings. The salt is giving you the high KH reading. This is an Ion exchange softener that charges the resin with salt rather than acid. The water from these type of units is not for drinking purposes and way too high in sodium for Discus. It's purpose is to shower in, and wash clothes in because of the increase of soap lather.
Household water softeners like yours that use salt to recharge are usually installed to work in bathrooms and dishwashers only. Check your water from your kitchen tap and see if you still get the same readings. If you do, I suggest that you replace it with a RO system or remove it completely.

Graham

11-28-2006, 03:04 PM

Hi Lisa.You are using a household water softener that is exchanging sodium for calcium and magnesium. That is the reason for your readings. The salt is giving you the high KH reading. This is an Ion exchange softener that charges the resin with salt rather than acid. The water from these type of units is not for drinking purposes and way too high in sodium for Discus. It's purpose is to shower in, and wash clothes in because of the increase of soap lather.
Household water softeners like yours that use salt to recharge are usually installed to work in bathrooms and dishwashers only. Check your water from your kitchen tap and see if you still get the same readings. If you do, I suggest that you replace it with a RO system or remove it completely.

Annie how is the salt/ Sodium chloride giving her high KH readings...KH read carbonates at high pH and bicarbonates at lower pH's

http://www.lenntech.com/water-softener-FAQ.htm#3

5.2 Is softened water safe to drink?

Softened water still contains all the natural minerals that we need. It is only deprived off its calcium and magnesium contents, and some sodium is added during the softening process. That is why in most cases, softened water is perfectly safe to drink. It is advisable that softened water contains only up to 300mg/L of sodium.
In areas with very high hardness the softened water must not be used for the preparation of baby-milk, due to the high sodium contant after the softening process has been carried out.

annieb

11-28-2006, 06:55 PM

Annie how is the salt/ Sodium chloride giving her high KH readings...KH read carbonates at high pH and bicarbonates at lower pH's

I don't want to debate with you, Graham. She's probably using a household salt exchange system thats' loading her water with sodium. Much too much sodium for her Discus and much to much sodium to drink on a regular basis. Apparantly, the sodium in the water is raising KH without affecting GH. The GH is of course very low because the unit is exchanging calcium and magnesium for sodium chloride.
If you don't agree, that fine. I hope for her sake she does.

White Worm

11-28-2006, 07:09 PM

So, have you guys voted on the Glowing discus poll yet? :D

Graham

11-28-2006, 09:16 PM

Apparantly, the sodium in the water is raising KH without affecting GH. The GH is of course very low because the unit is exchanging calcium and magnesium for sodium chloride.

Annie this isn't a debate where there are opinions, this is chemistry and the laws of chemistry apply............. The amount of sodium that discus and people can take may be open for debate, but that sodium is upping her KH levels isn't open for debate.

You are talking apples and oranges, Unless there is something that I missed in buffering chemistry, sodium isn't going to affect KH levels, which are based on carbonates and bicarbonates, usually read as CaCO3/calcium carbonate.

Mike I like real things...I'll take a wild over a man made anyday:antlers:

G

White Worm

11-29-2006, 12:07 AM

I'm sure they could make a heckels middle bar glow :D wouldnt that be somethin'?

fishmama

11-29-2006, 01:47 AM

Okay Mikscus...you naughty, naughty thing, back to the thread. You will be getting a lump of coal in your stocking this year!

Okay...let's just say hypothetically, you have a "show tank" with adults and no plants. OKAY-well, maybe not "hypothetical."

You have NO OPTION
because if I put a huge ol' RO tank in our jacuzzi my hubby will have a cow and send me packing!

Thus, your water MUST come via water softener. I have "turned our down" to the lowest setting. Meaning the incoming water is only minimally altered.

BTW...PLEASE do not tell aforementioned hubby I did that!

So...incoming water passes over charged resin beads and removes some (because I am on "low" setting") Ca+ and Mg+, hence putting in to my supply Na+ (NOT TO BE CONFUSED WITH*NaCl)!!!!!!!!!!!

TDS is TDS...correct???? Doesn't matter if the hardness comes from Ca+ and Mg+ or other DOC's and/or inorganic compounds.

My TDS starts at 325 and ends the same pre and post "softener."

I also realize that if fish prefer "soft", it doesn't matter if it is Ca+, Mg+ or "other."

So why...biochemically speaking...does that effect mature discus? They were breed and born in this same water, without going over softener. Has anyone out there tried "ADJUSTING" their household softener to fit the needs of discus?

I suspect it may have something to do with OSMOREGULATION.

Thanks,
Lisa

fishmama

11-29-2006, 02:06 AM

Polar_Bear

11-29-2006, 03:02 AM

The left overs can be anyone of a number of different things, including organics such as carbohydrates, fats, amino acids, anything that forms organic carbons....DOC's

I wish this were actually true, it would make my life much simpler. Unfortunately Conductivity meters don't measure carbon, they measure salts, in our case mineral salts, or put another way, metalic ions. I do definately agree with Graham that DOC are bad, and also with most else he has said.

All conductivity meters work a little differently from each other. The ratio I usually use is multiplying TDS by 0.657 to get micro seimens, but this is only an approximation in any case and Annie's is close enough and much simpler. If you wish to know what your manufacturer uses, most include it with their instructions or on their web site, if that fails e-mail them and you should get an answer.

raglanroad

11-29-2006, 08:17 AM

http://www.4oakton.com/Con_to_TDS.htm yes, PolarBear, the .65 approx. figure is related to most river water composition and thus is a good guess for "converting" from ms conductivity to ppm TDS in most cases.
which way does the conversion work, though ? - from ppmTDS to ms conductivity or from ms conductivity to ppm TDS, when using that formula ?
I think it is from ms conductivity to ppm TDS, and the formula can be .65 x conductivity = TDS.
the charts show how TDS is not really just conductivity being read in a different way.
we use a trick -a similar trick to guessing weight by height. There is there is a pretty strong correlation, but they are not the same thing at all.
By knowing that all persons tested are about the same build (most river and lake waters are similar in ionic composition ), however, we can be fairly accurate in guessing.

Note that as TDS goes really high, the conductivity does not rise correspondingly. The "guess" conversion factor does not remain fixed - .65 or any simple conversion does not apply across the board if we look at super "hard"water. It applies as a guess in the normal ranges we work with.

Note that in TDS for solution of KCl is not the same as for NaCl, with ms held constant.

Note that for convenience we use the "m" instead of the "mu" symbol when we write "ms". ms is a bigger unit of measurement, you can see it at the bottom of the chart.

raglanroad

11-29-2006, 09:17 AM

Hey Graham-

Thanks for clarifying TDS...for some reason I thought TDS was only dissolved inorganic compounds. I didn't realize is included organics.

LisaLisa, for your full appreciation of the situation, may I suggest you verify the information given by adding two heaping spoons of sugar to a cup of your test water and see what happens to the reading. ... : ) : ) : )

grab a coffee and and have your morning chuckle while you're at it.

fishmama

11-29-2006, 09:52 AM

ooohhhhh...how fun...it's freshman chem lab all over again!!!

seriously though, my kids would think mom is pretty cool running experiments and they might learn something too!

raglanroad

11-29-2006, 10:34 AM

yeah, true, !
I tested sugar and tapwater, sugar and RO water, sugar and kent cichlid salt reconstituted water. : ) I won't spoil your fun by telling the results.

korbi_doc

11-29-2006, 10:48 AM

Hi Dottie-

WOW! 900+ppm TDS, I'm duly humbled!!!!

Just wondering...what type of household water softener did you have? Potassium based or Sodium based exchange?

BTW-your avatar rocks! I miss my equus days...not sure which is more costly, fish or horse!!!

Lisa

Hi Lisa, the softener was definitely Sodium based exchange & this is NOT good water for discus, unfortunately I proved that to myself, & wound up using 100% R/O, a pia, but it worked, tho I felt like a true chemist when I reconstituted the water in tubs, lol....think the Potassium based might be better, don't know tho, since I never tried it & haven't heard from anyone using it...

Thanks re avatar; I can tell you which is more costly, the Horse! But then I do have 4, so that skewes the curve; maybe with just 1, the fish would win out, lol; why do I always wind up with the "outsider" types of animal: Doberman Pinscher: Arabian: Discus! LOL!, Dottie ;)

Squiggy

11-29-2006, 02:16 PM

I'd sure hate having to vacuum the horse's tank....:crazy:

White Worm

11-29-2006, 02:31 PM

Okay Mikscus...you naughty, naughty thing, back to the thread. You will be getting a lump of coal in your stocking this year!

Ahhhh mama, I dont want no coal :D Maybe a corvette if you have one of those in your xmas goody bag? OK, OK, back to the topic. :)
<<---------scolded :p

raglanroad

11-30-2006, 11:03 AM

any results showing for Graham's assertion that dissolved organic carbons show properly as readings on conductivity or
TDS meters, Mama ?

fishmama

11-30-2006, 11:14 AM

Hi Raglan-

Not yet, but the kids are out of school today due to bad weather, so thought it would be fun for them to "help me out"!

Will post once I get some results! They will probably want to measure Kool-Aid!

raglanroad

11-30-2006, 11:20 AM

It is my understanding that the "water softener" is an ion exchange resin...thus it only exchanges 1 to 1 ratio. The Na+ takes the place of either Ca+ or Mg+, and I would expect the TDS reading to remain the same. Is that correct?

LisaLisa, the conductivity is what is being measured by the TDS meter.
Ca has a different characterisitic for conductivity in solution than Na.
Therefore, the conductivity readings for Na solution will be different than for Ca solution, and so a different conductivity value is given by the meter.

Multiplying the conductivity value to convert to ppmTDS also keeps the illusion intact.

Re testing:

Yeah, I predict it offers a great perspective on the validity of some of the pronouncements made... to be taken with a "dash of salt" and all that TDS. : )

fishmama

11-30-2006, 11:54 AM

Okay, here are the "results" per Hanna Primo Microprocessor Conductivity & TDS Meter with Auto Temp Compensation: rinsed w/RO between solutions:

RO-69
RO w/lots of sugar dissolved-55 (decreased conductivity, wow, I was not expecting that)
Tap-262
Community Tank-322 (could this increase be due to buffer/conditioner?)
Cold Soy Milk-1985+caused the meter to go "off" the chart
Hot Coffee made with RO-430

And then my son decided to stick the meter in his mouth...reading, 0 he tells me ;-)

Any conclusions ya'll?

fishmama

11-30-2006, 11:57 AM

Raglan-

re: Ca and Na conductivty values, that makes perfect sense. I need a periodical chart!!

Thanks,
Lisa

raglanroad

11-30-2006, 12:04 PM

brewmaster15

11-30-2006, 01:45 PM

All,
I don't know exactly what is going on here and in other threads but I am seeing something that Is not going to lead to anything other than headaches for all involved.

What I see is disagreeing points of view, expressed poorly and in a deliberately antagonistic fashion. Whats started out as disgreements though is now spiraling into an all out personal attack and counter attack....I am seeing arguements and vendettas carried across threads..Threads have been locked already and others will follow. This is not productive and does nothing to promote healthy discussions.

I think in the 3 weeks we were shut down some have forgotten what this forum asks of its members.....

In a nutshell I would like to remind you all to disagree but discuss it in civil fashion, and by all means stand your ground if you feel your are right...but at no point should things become a personal attack based on a difference of opinion or Interpreted facts.

I think all involved need to take a step back and examine how they are presenting themselves to the forum....and perhaps try to tone it down and be more respective of each other.

I am availible if anyone wants to talk with me about this issue, but I have to be honest...I shouldn't have to... as Adults we should be able to deal with one another in a civil fashion , even when we disagree.

Thanks in advance,
al

please think of this as a warning everyone, I am nicely asking everyone to calm down.

fishmama

11-30-2006, 02:02 PM

Hey Al-

I guess I'm a bit clueless, but I purely am interested in the chemistry behind it all. Not trying to be antagonistic, and I certainly respect and value
EVERYONE'S experience and opinions. Nothing here in my mind to get amped up about. Sorry if it was taken that way.

Lisa

raglanroad

11-30-2006, 02:14 PM

my point is to try and show that this complex problem is not so simple as claimed, it is not understood well ,and we should present evidence to reach understanding. You have presented evidence with your readings that the conductivity test meters are not properly reading some dissolved organic carbons as ppm TDS or as ms conductivity.
This experiment is repeatable by others, and is thus superior evidence, over a mere unsupported claim ( which is no proof or evidence ).

P.S. hoping we can explore this further, to the point of gaining at least understanding of where we have got capability to make reasonable assumptions and where we don't

raglanroad

11-30-2006, 02:47 PM

Lisa, judging by your enthusiasm for finding out what's real, I bet you could turn this into a great sticky thread by experimentation into the questions of just what are we reading on the meters...and on some of the interactions the different compounds may have on conductivity readings, regardless of if this is true TDS or not.

After all, the meter is used as our practical representation of "TDS", and is the reading we deal with, we don't use the dehydrating test for TDS in the hobby.

Perhaps by starting with pure water, and adding a known selection of salts, we can compare TDS, and hardness as indicated by the test kits with known mineral soutions. Maybe we will notice where ( which salt solution is affected) sugar actually decreases the reading ?

Sounds like your young scientists might produce results !

Graham

11-30-2006, 02:49 PM

Lisa if the element doesn't have an electrical charge then it won't be picked up by the meter....sugar has a neutral charge therefore won't be picked up by the meter.....

Some interesting reading

''.......Koiphen Post by Dr Roddy Conrod….. PhD Chemistry…Dow chemical

A TDS meter measures the conductivity of the water. The main contributor to the conductivity of the water is the salt content. DOC is a very minor contributor to the conductivity, which is what the TDS meter measures.

So In My Opinion, all the TDS meter is going to tell you is the overall salt content of the water.

A salt meter is the exact same thing as a TDS meter, meaning both measure the conductivity of the water, then each has slightly different calibrations of how they express the conductivity in units more familiar to a ponding hobbyist. A salt meter is calibrated to read the conductivity as sodium chloride salt, a TDS meter is calibrated slightly differently to read the conductivity as the total dissolved salt content, meaning calcium and magnesium salts as well as sodium salts.

I would not give you a dime for the difference between a salt meter and a TDS meter, since they measure the same thing.
================================================== ===

http://www.yumekoi.com/articles/aug_2003.pdf

================================================== ==

Quote:
http://bcn.boulder.co.us/basin/data/BACT/info/TSS.html
Measurement of Total Dissolved Solids
To measure TDS, the water sample is filtered, and then the filtrate (the water that passes through the filter) is evaporated in a C, until the weight of the dish nopre-weighed dish and dried in an oven at 180 longer changes. The increase in weight of the dish represents the total dissolved solids, and is reported in milligrams per liter (mg/l).
The TDS concentration of a water sample can be estimated from specific conductance if a linear correlation between the two parameters is first established. Depending on the chemistry of the water, TDS (in mg/l) can be estimated by multiplying specific conductance (in micromhos/cm) by a factor between 0.55 and 0.75.
TDS can also be determined by measuring individual ions and adding them up

''....... This material can include carbonate, bicarbonate, chloride, sulfate, phosphate, nitrate, calcium, magnesium, sodium, organic ions, and other ions. .......''

http://en.wikipedia.org/wiki/Total_dissolved_solids
Total dissolved solids is an expression for the combined content of all inorganic and organic substances contained in a liquid which are present in a molecular, ionized or micro-granular (colloidal sol) suspended form. Generally the operational definition is that the solids (often abbreviated TDS) must be small enough to survive filtration through a sieve size of two micrometres. Total dissolved solids are normally only discussed for freshwater systems, since salinity comprises some of the ions constituting the definition of TDS.

http://www.hc-sc.gc.ca/ewh-semt/pubs...t/index_e.html
Definition
Total dissolved solids (TDS) comprise inorganic salts and small amounts of organic matter that are dissolved in water. The principal constituents are usually the cations calcium, magnesium, sodium and potassium and the anions carbonate, bicarbonate, chloride, sulphate and, particularly in groundwater, nitrate (from agricultural use).

http://www.reefkeeping.com/issues/2004-04/rhf/feature/index.php
What Does a TDS Meter Actually Detect?
Since TDS meters are often used to test water "purity," it is important to understand what they do not detect. As conductivity meters in disguise, TDS meters will only detect mobile charged ions. They will not detect any neutral (uncharged) compounds. Such compounds include sugar, alcohol, many organics (including many pesticides and their residues), and unionized forms of silica, ammonia, and carbon dioxide. These meters also do not detect macroscopic particulates, as those are too large to move in the electric fields applied. So if you see "rusty" looking water from iron oxide particulates, that won't be measured. Neither will anything else that makes the water look cloudy. Bacteria and viruses also won't be detected.
================================================== =

raglanroad

11-30-2006, 03:04 PM

...

Lisa, when it is observed that the readings go down after addition of sugar, could it mean that sugar or part thereof combines and offers a new compound, subtracting some conductive ion from the water column ?
just a guess tho

another guess...the addition of sugar gave a type of blocking of conductivity of the salt solution ?

sublevel007

11-30-2006, 04:34 PM

WOW, that is a lot of info guys thanks! I almost forgot I put this thread up the other day. I hope veeryone gets the info they needed out of it, I did!

fishmama

11-30-2006, 05:48 PM

Hi again-

Yes, this is tons of info and I have just enough knowledge to be dangerous, but not accurate ;-)

Graham-wish I had more time to read those links, I will have to come back to those tomorrow. They look very, very good. There is so much spinning around in my head today that I think I am getting dizzy ;-)

Raglan-I do think understanding these properties helps us in the long run to manipulate the discus environment properly. Part of the problem I am having is it seems that a lot of times we assume things that aren't applicable in all situations.

Gotta go...water changes to do!!!! And kiddos to feed!