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fastlane
9th Oct 2009, 03:29 PM
I know this topic has been discussed a few times. But I am still a little confused about this? I am using Mosura Mineral Plus to rise GH. But the Assa website says 150 - 220 TDS. My current paremeters are as follows.

PH 7.0
KH 2
GH 4
TDS 143

So with GH 4 do I still focus on rising the TDS to 150? I am worried that if I continue to rise TDS with Mosura, sometime might happen. Or it is ok to just achieve the GH and neglect the TDS part? My tap water TDS is 60.

Any expert can help?

imke_j
9th Oct 2009, 03:43 PM
If you GH stays stable, I would not rise TDS higher.

fastlane
9th Oct 2009, 05:04 PM
Thanks. So you mean, this TDS is ok? Even after WC, I will just add the minimum mineral plus to keep TDS and GH at this level?

sazuka
9th Oct 2009, 05:29 PM
GH are more important than TDS.
:)

imke_j
9th Oct 2009, 05:50 PM
GH are more important than TDS.
:)
Right: The GH is needed to stabilze the pH and avoid acid downfall. F. e. the formerly found Princess Bee (/blog/new-shrimp-from-vietnam/) from Vietnam live naturally in TDS 24.

silane
9th Oct 2009, 08:07 PM
hmm... I thought kH is the one to prevent slide of pH?

Frank
9th Oct 2009, 11:22 PM
GH 4 is a bit low for my taste. :undecided

Justin12345
9th Oct 2009, 11:47 PM
Can anyone further explain the meaning of TDS?
sorry about this.
I try reading wiki but the explaination is not what i could understand
from when i digested from wiki is that High TDS is hard water and TDS contains inorganic and organic substance. I dont quite relatively understand this . So can i say its the same as ph?

silane
10th Oct 2009, 07:45 AM
GH 4 is a bit low for my taste. :undecided

As far as CRS is concerned, the trend is keeping them at high GH, even though bee shrimps natural enviroment GH can be very low like 1 or almost undetectable.

4 is the minimal for the trend now. I alway has problem trying to use water parameter to emulate the wild condition for those wild caught shrimp.

But again, this figure has to do with the soil one is using and the water source.

silane
10th Oct 2009, 07:46 AM
Can anyone further explain the meaning of TDS?
sorry about this.
I try reading wiki but the explaination is not what i could understand
from when i digested from wiki is that High TDS is hard water and TDS contains inorganic and organic substance. I dont quite relatively understand this . So can i say its the same as ph?

There are many writeup on TDS beside wiki, you have to read the basic there and then we can discus what is TDS for shrimps.

louuu
11th Oct 2009, 03:26 AM
Can anyone further explain the meaning of TDS?
sorry about this.
I try reading wiki but the explaination is not what i could understand
from when i digested from wiki is that High TDS is hard water and TDS contains inorganic and organic substance. I dont quite relatively understand this . So can i say its the same as ph?

Not sure if this will help...

(TDS) simply put...
TDS content of a water is the most common measure of its overall degree of mineralization... i.e. literally a measure of everything that is dissolved in the water... Generally a portion of the minerals that are dissolved in water are calcium and magnesium... the ions that make up water hardness... It is also the best measure of salinity (not alkalinity)...
However... the general notion that the higher the TDS, the higher the total hardness... is not always true...
Many times a high sodium concentration in the water will yield a high TDS and salinity but the water will have a low hardness concentration because sodium does not add hardness to the water...

---------------------------------------------------------------------
Here's something about alkalinity n hardness...

The hardness of a water is a reflection of the concentration of calcium and magnesium ions in solution...
The total hardness of a water is often subdivided into 2 components, namely...
Temporary hardness - which can be removed by boiling... during which the Ca and Mg combine with the bicarbonate alkalinity in the water to precipitate carbonate scales...
and...
Permanent hardness - which remains even after boiling...

Given that temporary hardness depends on the availability of alkalinity... a summary for distinguishing between temporary n permanent hardness can be made as follows:

If there is no alkalinity... all hardness is permanent hardness...
If alkalinity exceeds total hardness... all of the hardness is temporary... i.e. there is zero permanent hardness...
If total hardness exceeds alkalinity... then temporary hardness = alkalinity... and permanent hardness = the difference between total hardness and alkalinity...

Justin12345
11th Oct 2009, 08:18 AM
Not sure if this will help...

(TDS) simply put...
TDS content of a water is the most common measure of its overall degree of mineralization... i.e. literally a measure of everything that is dissolved in the water... Generally a portion of the minerals that are dissolved in water are calcium and magnesium... the ions that make up water hardness... It is also the best measure of salinity (not alkalinity)...
However... the general notion that the higher the TDS, the higher the total hardness... is not always true...
Many times a high sodium concentration in the water will yield a high TDS and salinity but the water will have a low hardness concentration because sodium does not add hardness to the water...

---------------------------------------------------------------------
Here's something about alkalinity n hardness...

The hardness of a water is a reflection of the concentration of calcium and magnesium ions in solution...
The total hardness of a water is often subdivided into 2 components, namely...
Temporary hardness - which can be removed by boiling... during which the Ca and Mg combine with the bicarbonate alkalinity in the water to precipitate carbonate scales...
and...
Permanent hardness - which remains even after boiling...

Given that temporary hardness depends on the availability of alkalinity... a summary for distinguishing between temporary n permanent hardness can be made as follows:

If there is no alkalinity... all hardness is permanent hardness...
If alkalinity exceeds total hardness... all of the hardness is temporary... i.e. there is zero permanent hardness...
If total hardness exceeds alkalinity... then temporary hardness = alkalinity... and permanent hardness = the difference between total hardness and alkalinity...


Thanks Lou for the info

louuu
11th Oct 2009, 04:10 PM
Thanks Lou for the info

U r welcome Justin,

Was quite late last night... hence did not attempt to answer fastlanes's question... not sure if i can simplify things for him/her... but i'll give it a shot...

Since we can all agree that the hardness of water is related to the overall dissolved minerals it contains... then, loosely put... the total hardness is usually regarded as comprising of two components:
General hardness (GH) - caused by divalent metal ions... primarily calcium and magnesium...
and...
Carbonate hardness (KH) - due to carbonate/bicarbonate ions... and represents the main "buffering capacity" of the water... i.e. its ability to resist pH changes...

Carbonate hardness (KH) is sometimes referred to as temporary hardness... because it can be removed by boiling... which precipitates into carbonates scales...
The remaining hardness contributed by other salts of calcium and magnesium is then referred to as permanent hardness (or non-carbonate hardness)...

-----------------------------------------------------------------------

If we r also in agreement that...
Total Dissolved Solids (TDS) - refers to a measure of all the inorganic solids dissolved in the water... so it will not only measure ions which contribute to hardness, like calcium... but also those that do not, like sodium... It is therefore a better reflection of the total mineral content of the water than hardness measurements alone...

--------------------------------------------------------------------------

Most commercial GH test kits measure the calcium and magnesium salts present in the aquarium water but not the sodium salts as it is not a hardening salt...
whereas...
TDS is derived from the related conductivity measurement (method most accessible to aquarists)... more accurate measurement can be determined by the "dry weight" of solids left after evaporating the water under laboratory conditions... i.e. a measurement of all salts present in the water...

--------------------------------------------------------------------------

Hence... an appropriate answer to fastlane's query would be...


YES... there is an inter-relationship between GH and TDS measurement results of the water tested...
NO... TDS measurement results is not an accurate indication of GH values in the water tested...


Conclusion:
Depending on which "salts/ions/elements" u desire to be present in the water... which in this case, i presume, its Ca and Mg... then the GH value will be the objective... the TDS readings however will indicate all the "GH ions" + "other ions" present in the water, which may or may not be desirable... and the control here would be to obtain the required GH values while keeping the other ions within your required range...

hope it helps... as it's trying to explain chemistry in layman's term... :embarasse

retardo
11th Oct 2009, 04:13 PM
hmm... I thought kH is the one to prevent slide of pH?

This is correct. KH is the buffering agent, not GH.

retardo
11th Oct 2009, 04:21 PM
I know this topic has been discussed a few times. But I am still a little confused about this? I am using Mosura Mineral Plus to rise GH. But the Assa website says 150 - 220 TDS. My current paremeters are as follows.

PH 7.0
KH 2
GH 4
TDS 143

So with GH 4 do I still focus on rising the TDS to 150? I am worried that if I continue to rise TDS with Mosura, sometime might happen. Or it is ok to just achieve the GH and neglect the TDS part? My tap water TDS is 60.

Any expert can help?

Here is an article (http://www.shrimpnow.com/viewarticle.php?articleid=73) in the library that may help. It does not cover TDS values, which IMO, are not as important. KH is recommended to be at a minimum of 3 to be considered stable. However, if your shrimp are doing well in the tank, then don't change anything. The more you tinker with the water, the more problems you may get.

fastlane
11th Oct 2009, 09:38 PM
Thank you all. Actually my specific question is with regards to GH and TDS and Minernal plus dosing for CRS . I do understand the basics of GH and TDS. But from the forums, there are two schools on mineral dosing. One says that to monitor the GH only. And another measures only TDS, from TDS they could estimate the GH. Silane mention that GH 4 is the mininal. But if I increase GH using Mosura or Mineral power, I would be increasing TDS at the same time. I also read that high TDS is toxic for higher PH. My PH is 7. So I am worried. I have been getting a few deaths here and there from time to time. So I am wondering if it is my GH and TDS problem. Assa says TDS 150 - 220 using Mosura Mineral Plus. I am confused.

Frank
12th Oct 2009, 04:37 AM
Low GH could be a reason.
I also need to rise the hardness and go for GH around 6-7.
My KH is around 3-4.
Until the hardness is rised all my inverts seem to feel better.
To work with TDS needs some experience.
You better note the "normal" parameters in the first place.

fastlane
12th Oct 2009, 11:12 AM
Thank I am using Shinkura Mineral Power to rise GH. Will it be harmful if I rise 4 - 6 GH within a 24hrs period. GH will not affect PH right?

Frank
12th Oct 2009, 03:07 PM
Thank I am using Shinkura Mineral Power to rise GH. Will it be harmful if I rise 4 - 6 GH within a 24hrs period. GH will not affect PH right?

Proably it works but 0,5° each day is safer.
GH doesnīt affect PH, thatīs right.
Most problems with low GH appear by molting.
Itīs easier for the shrimps to take the needed Minerals from food, but IMO itīs safer with GH as well.
I propose to dose until the wanted value is reached and with next Waterchange you add Minerals for the amount of new tap water.
Measure the Parameters KH/GH/PH from time to time and see if your shrimps feel better.

wifi
12th Oct 2009, 10:07 PM
Thank I am using Shinkura Mineral Power to rise GH. Will it be harmful if I rise 4 - 6 GH within a 24hrs period. GH will not affect PH right?

I would prefer to use Mosura Mineral Plus, liquid form, it is safe and does not affect pH for sure. I think 1 day increase by 1 GH is better, less stress for your shrimps.

fastlane
13th Oct 2009, 02:23 PM
I have been adding Mosura Mineral Plus but the GH doesn't seems to move at all. But the TDS keep going up.

fastlane
13th Oct 2009, 02:30 PM
I have been using mineral plus but the GH doesn't move at all. And the TDS keeps going up. Any advise? There are also other minerals and iodine in mineral plus. Any risk of overdosing?

mopas
12th Nov 2009, 04:54 PM
check youre gh kit. maybe out of date?

retardo
13th Nov 2009, 05:16 AM
I have been using mineral plus but the GH doesn't move at all. And the TDS keeps going up. Any advise? There are also other minerals and iodine in mineral plus. Any risk of overdosing?

What is your water change schedule/routine? Are you topping off, mixing RO/tap, other?

I have not used Mosura Mineral Plus before, but as I understand it, it is supposed to affect the GH to some degree. Any time you add something to the water (e.g., water conditioner, plant ferts, food you feed your shrimp/fish), the TDS will rise. There is no reason why it wouldn't. There is a tipping point where your water will become "toxic", but if you do regular water changes, you certainly limit the amount of TDS that build up in the water. If we were to look at TDS on linear scale, it would look like this: fresh water < 1500 mg/L TDS < brackish water < 5000 mg/L TDS < saline water. I have no idea what the chemical composition of the Mineral Plus is, but I would imagine that it would not be enough to change the water to a point where it would wipe out your shrimp population if you follow the instructions.