# Lowering tds...



## plantnoobdude (28 Feb 2022)

At the moment my tds floats around 100 in my high tech tank, around 65 of it is from my remineraliser. I want to get this lower, the majority of my tds is made up of relatively useless cl and S
because of this I want to get rid of it, I will stop using K2so4 by swapping it out for kno3. and now I want to deal with my remineraliser where the bulk of cl and s comes from. 
I was thinking whether or not I could use caco3 and mgco3 and then react the co3 with hcl to get kh less water with lower so4 and cl, but I am wondering whether or not there will be more cl from hcl than originally in cacl? anyone with insights on this topic? cheers,


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## Hanuman (1 Mar 2022)

Hi,
Have you used the IFC calculator? You could play around to see which provides more or less.

If I may, what is the rational to reduce your TDS so low? 65 TDS for remin is already rather on the low side.  What are your current remin targets and dosage?

Have a look at this Remineralizing question


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## Maf 2500 (1 Mar 2022)

Combine your ferts with your remineralistion and make use of calcium nitrate, magnesium nitrate, potassium nitrate etc. No chlorides or sulphates.


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## MichaelJ (1 Mar 2022)

plantnoobdude said:


> At the moment my tds floats around 100 in my high tech tank, around 65 of it is from my remineraliser. I want to get this lower, the majority of my tds is made up of relatively useless cl and S
> because of this I want to get rid of it, I will stop using K2so4 by swapping it out for kno3. and now I want to deal with my remineraliser where the bulk of cl and s comes from.
> I was thinking whether or not I could use caco3 and mgco3 and then react the co3 with hcl to get kh less water with lower so4 and cl, but I am wondering whether or not there will be more cl from hcl than originally in cacl? anyone with insights on this topic? cheers,


Hi @plantnoobdude   By " 65 of it is from my remineraliser" I assume you mean from CaCl2 or CaSO4, MgSO4 to raise your GH... I've been there.  Look into Ca Gluconate and Mg Gluconate. You might not want to go all-in on the Gluconate, but you can easily use quite a bit of Ca and Mg Gluconate to shave off a lot of that excess SO4 or Cl (you do need "some" S and Cl though). I've been doing that for a while now with no negative side effects so far.

Just as an example for Ca:

If you target 20 ppm of Ca with CaCl2 you get 35 ppm of C   a total of 55 ppm.
If you target 20 ppm of Ca with CaSO4 you get  16 ppm of S a total of 36 ppm. (Note: CaSO4 is less soluble than CaCl2, but its a total non-issue unless you're targeting unrealistic high Ca levels).
If you target 20 ppm of Ca with Ca Gluconate you only get the 20 ppm of Ca with nothing else that will raise TDS... However, you will be getting a lot of Gluconate - which is a glucose derivative (sugar) and organic compound that may possibly trigger bacterial blooms if used in excess  - which happened to me in the past because I went overboard.

My recommendation  would be to target half of your Ca needs with Ca Gluconate and the rest with CaSO4 (perhaps with a little bit of CaCl2 mixed in if your not not getting any Cl from other sources) - and likewise half your Mg needs with Mg Gluconate and the rest with MgSO4 or even better, depending on your NPK targets, MgNO3. That should shave off a lot of TDS.

Getting the TDS down while making sure you get all the necessary Ca, Mg and NPK takes a bit of juggling.  But using @Hanuman /  @Zeus.  excellent IFC Calculator should get your there without too much trouble.


Cheers,
Michael


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## plantnoobdude (1 Mar 2022)

Hanuman said:


> Have you used the IFC calculator? You could play around to see which provides more or less.


I am using the Ifc calculator.


Hanuman said:


> If I may, what is the rational to reduce your TDS so low? 65 TDS for remin is already rather on the low side. What are your current remin targets and dosage?


for fun to get the water with as little "stuff" in it as possible.
18ppm Ca and 6ppm Mg from cacl2h2o and Mgso47h2o is what I use.


Maf 2500 said:


> Combine your ferts with your remineralistion and make use of calcium nitrate, magnesium nitrate, potassium nitrate etc. No chlorides or sulphates.


I do not want too much No3 in the water as I am using Urea for N.



MichaelJ said:


> but you can easily use quite a bit of Ca and Mg Gluconate to shave off a lot of that excess SO4 or Cl (you do need "some" S and Cl though


It does seem good but, the bacterial blooms do not appeal to me as well as the fact that I won't to be able to get that much off of it.

I also cannot seem to find Mg and Ca gluconate in pure forms, most of it seems to be sold as a part of a pill.


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## MichaelJ (1 Mar 2022)

plantnoobdude said:


> It does seem good but, the bacterial blooms do not appeal to me as well as the fact that I won't to be able to get that much off of it.


Hi @plantnoobdude  I  hear you.  I never really understood what happened in my case when I used a lot of it and I got very cloudy water -  was it a bacterial bloom, precipitation of sorts or other interaction? I have no idea. My guess is a bacteria bloom considering the organic matter (sugar) that makes up the Gluconate.  When I finally figured out the amounts of Ca and Mg Gluconate that was "safe" in the sense that I no longer got cloudy waters I did get quite a bit of milage out of it though - and was able to shave off 30 ppm or so of my TDS (vs the 100% use of MgSO4 and CaSO4)... whether thats worthwhile obviously depends on what you want to achieve etc.  What compounds are you using right now for remineralization? and what Ca and Mg ppms are you targeting?

I have noticed that at least one reputable fertilizer company have started using Gluconate in their remineralizers such as Nilocg Regen GH Booster.  How much they are using, and how well its been researched I do not know.



plantnoobdude said:


> I also cannot seem to find Mg and Ca gluconate in pure forms, most of it seems to be sold as a part of a pill.



I am using this powder-form product for Ca Gluconate. They have a similar product for Mg.

Cheers,
Michael


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## plantnoobdude (1 Mar 2022)

MichaelJ said:


> whether thats worthwhile obviously depends on what you want to achieve etc. What compounds are you using right now for remineralization? and what Ca and Mg ppms are you targeting?


cacl and mgso4. targeting 18ppm Ca and 6ppm Mg. 

I was thinking Hcl would work well, but i'm not sure how much cl would be added in the progress...


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## MichaelJ (1 Mar 2022)

plantnoobdude said:


> cacl and mgso4. targeting 18ppm Ca and 6ppm Mg.


You could go CaSO4 instead of CaCl2 - just that  would shave off ~17.5 ppm of TDS for the same amount of Ca.

Cheers,
Michael


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## plantnoobdude (1 Mar 2022)

MichaelJ said:


> You could go CaSO4 instead of CaCl2 - just that  would shave off ~17.5 ppm of TDS for the same amount of Ca.
> 
> Cheers,
> Michael


yes, true. apparently so4 is a less troublesome anion than cl in our tanks, I dose my remineraliser in liquid form,but i probably wouldnt be able to do that with caso4.
probably will add 0.1ppm or so of cl as well from an alternative source.
but 20ppm or so isn't exactly game changing, still looking for an alternative.... good ca, mg and very little cl and s


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## MichaelJ (1 Mar 2022)

plantnoobdude said:


> yes, true. apparently so4 is a less troublesome anion than cl in our tanks, I dose my remineraliser in liquid form,but i probably wouldnt be able to do that with caso4.


Hi @plantnoobdude  I never experimented much with liquid dosing of remineralizers. I always thought it was too problematic due to solubility and precipitation issues in the mixing bottle.  Also, I never had any issues weighting everything out on a microgram scale and just mix it in with my WC water - takes me a minute or two during WC. 


plantnoobdude said:


> probably will add 0.1ppm or so of cl as well from an alternative source.
> but 20ppm or so isn't exactly game changing, still looking for an alternative.... good ca, mg and very little cl and s


Well, 65 to 45 ppm is a 30% reduction... thats not bad at all... With your target of 18 ppm of Ca and 6 ppm of Mg your really only left with 21 ppm of "unwanted" TDS and if you would add say 33% of the Ca target as Ca Gluconate you could shave off an additional 5 ppm of the unwanted TDS (you could do the same with Mg Gluconate vs. MgSO4), and bring your total TDS contribution from remineralizers down to 38-40 ppm...  I don't see what much else you can do to shave off TDS from the remineralizers except lowering your Ca and Mg targets in general.

Cheers,
Michael


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## plantnoobdude (1 Mar 2022)

MichaelJ said:


> Hi @plantnoobdude  I never experimented much with liquid dosing of remineralizers. I always thought it was too problematic due to solubility and precipitation issues in the mixing bottle.  Also, I never had any issues weighting everything out on a microgram scale and just mix it in with my WC water - takes me a minute or two during WC.
> 
> Well, 65 to 45 ppm is a 30% reduction... thats not bad at all... With your target of 18 ppm of Ca and 6 ppm of Mg your really only left with 21 ppm of "unwanted" TDS and if you would add say 33% of the Ca target as Ca Gluconate you could shave off an additional 5 ppm of the unwanted TDS (you could do the same with Mg Gluconate vs. MgSO4), and bring your total TDS contribution from remineralizers down to 38-40 ppm...  I don't see what much else you can do to shave off TDS from the remineralizers except lowering your Ca and Mg targets in general.
> 
> ...



liquid dosing I do with two separate solutions, one for ca on for Mg. when mixing cacl and mgso4, I believe it precipitates to form caso4 which is less soluble which is why it often forms white dust at the bottom of my dosing solution previously. solids at the bottom make it very difficult to accurately dose ca/mg at accurate amounts. with separate solutions it is much easier, more accuaret and takes maybe 2-3 seconds longer than one solution.

I will think about ca gluconate and caso4. could work well.  seems decent now that you've put the numbers right infront of me! thanks.


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## MichaelJ (1 Mar 2022)

Hi @plantnoobdude  How do you dose N/NO3 ? And what do you target?   ... I'm using Mg(NO3), so I am getting about 1/3rd of my Mg "budget" from Mg(NO3) (and 100% of my N/NO3).  Of course, if your targeting very low levels of N/NO3 its a moot point to use Mg(NO3)...

Cheers,
Michael


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## plantnoobdude (1 Mar 2022)

MichaelJ said:


> Hi @plantnoobdude  How do you dose N/NO3 ? And what do you target?   ... I'm using Mg(NO3), so I am getting about 1/3rd of my Mg "budget" from Mg(NO3) (and 100% of my N/NO3).  Of course, if your targeting very low levels of N/NO3 its a moot point to use Mg(NO3)...
> 
> Cheers,
> Michael


I am dosing Urea solely for N. though i have stopped as i suspect my 2-3 month old aquasoil was leaching more than I thought. in the past month or so I have used anywhere from 1ppm-3ppm N per week (~13ppm No3 equivelant) with the rest of nutrients at 0.39ppm P and 2ppm K


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## MichaelJ (1 Mar 2022)

plantnoobdude said:


> I am dosing Urea solely for N. though i have stopped as i suspect my 2-3 month old aquasoil was leaching more than I thought. in the past month or so I have used anywhere from 1ppm-3ppm N per week (~13ppm No3 equivelant) with the rest of nutrients at 0.39ppm P and 2ppm K


Hi @plantnoobdude  OK, right, there is not much leverage there for _piggybacking_ Ca/Mg on any of those compounds when in such small amounts.



plantnoobdude said:


> I will think about ca gluconate and caso4. could work well. seems decent now that you've put the numbers right infront of me! thanks.


Yes, I would suggest just doing everything with Ca Gluconate very slowly and monitor the reactions.  Start with say 10% and increase in 10% increments at each WC until you reach like 30-40% Ca Gluconate vs. CaSO4.

Cheers,
Michael


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## aquanoobie (16 Apr 2022)

plantnoobdude said:


> cacl and mgso4. targeting 18ppm Ca and 6ppm Mg.
> 
> I was thinking Hcl would work well, but i'm not sure how much cl would be added in the progress..


HCl will not change CaCl2 and MgSO4. HCl will lower your KH by removing HCO3 bicarbonate and release CO2 in the process, and, close your eyes, HCl will increase TDS.



Maf 2500 said:


> Combine your ferts with your remineralistion and make use of calcium nitrate, magnesium nitrate, potassium nitrate etc. No chlorides or sulphates.


Yes, this is the only way to lower TDS. Also you could consider lowering Ca and Mg. It doesn't have to be this high and lowering it makes significant change to the total TDS readings.


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## Djoko Sauza (16 Apr 2022)

Alternatively you could slowly reduce the amount of Ca and Mg you add until you reach a value you and your livestock are happy with?  You'd have to keep an eye on your plants of course but from personal experience we need much less GH than usually advised. My tank is currently at 40tds and plants still growing fine.


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## plantnoobdude (16 Apr 2022)

aquanoobie said:


> HCl will not change CaCl2 and MgSO4. HCl will lower your KH by removing HCO3 bicarbonate and release CO2 in the process, and, close your eyes, HCl will increase TDS.
> 
> 
> Yes, this is the only way to lower TDS. Also you could consider lowering Ca and Mg. It doesn't have to be this high and lowering it makes significant change to the total TDS readings.


HI, I was talking about using CaCo3 and Mgco3. then using HCl to get rid of co3, but I was wondering how much Cl that would add in the process. 
well, I have amano shrimp, so I need 4-6gh.


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## Aleman (16 Apr 2022)

Calcium chloride adds 2 chloride ions for each calcium ion. If you neutralise carbonate with HCl it will take 2 hydrogen ions to do so, which will leave 2 chloride ions ... So same thing really.

FWIW, calcium sulphate is soluble to 2.3g per litre so while it may be difficult to get it to dissolve in a bottle, it will dissolve freely in your water change volume ...


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## aquanoobie (16 Apr 2022)

plantnoobdude said:


> HI, I was talking about using CaCo3 and Mgco3. then using HCl to get rid of co3, but I was wondering how much Cl that would add in the process.
> well, I have amano shrimp, so I need 4-6gh.


Hi
Adding HCl replaces CO3 with Cl2 and by doing so increases TDS. CaCO3, MgCO3, CaSO4, MgSO4 have lower TDS than CaCl2 and MgCl2. I know you don't want NO3 but the lowest TDS can be done with CaNO3 and MgNO3, avoiding SO4, Cl2, CO3. But plants need S as an essential macronutrient so adding some is good. 

Since urea is organic molecule it does not increase TDS and it is an excellent N source. 

When you look at very low TDS natural waters you will also see very low Ca and Mg levels. There is no way around it. Higher Ca, Mg, GH comes with higher TDS.


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## Easternlethal (18 Apr 2022)

For those who play around with tds, what are the pros and cons in terms of plant health? 

I am exploring reducing kh in my tank to grow more difficult plants but don't have the option of remineralising RO so just using leaves/peat moss or HCl. Will high tds make it harder for plants and outweigh the benefits of lower ch?

Sent from my LM-V405 using Tapatalk


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## aquanoobie (18 Apr 2022)

Easternlethal said:


> I am exploring reducing kh in my tank to grow more difficult plants but don't have the option of remineralising RO so just using leaves/peat moss or HCl.


Leaves, peat moss and HCl lower KH, not TDS.


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## aquanoobie (18 Apr 2022)

Easternlethal said:


> Will high tds make it harder for plants and outweigh the benefits of lower ch?


Well, looking at your Hong Kong water report you have nothing to worry about. Your local report says 0.5 to 2.4 dKH, average 1.4 dKH.


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## Easternlethal (18 Apr 2022)

aquanoobie said:


> Leaves, peat moss and HCl lower KH, not TDS.


Yes I know - but one of the methods, hcl seems the most convenient for me but raises tds as has been pointed out so I just want to understand whether high tds would affect harder to grow plants like pantanal, syns etc

Yes HK kh is quite low because there's no limestone in this part of the world but I have seryu stones in my tank which can raise kh by as much as 5 (now hovering around 3) and I would like to get it down to 1 or less


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## aquanoobie (18 Apr 2022)

Easternlethal said:


> I just want to understand whether high tds would affect harder to grow plants like pantanal, syns etc


That depends on what ions are causing the TDS increase.



Easternlethal said:


> Yes HK kh is quite low because there's no limestone in this part of the world but I have seryu stones in my tank which can raise kh by as much as 5 (now hovering around 3) and I would like to get it down to 1 or less


If you inject CO2 on those stones than it is like pouring hot water on ice cream. CO2 in -> KH out, that's how the stones work.


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## Easternlethal (18 Apr 2022)

Yes - i used some of it it to prop up substrate when I put my tank together before anticipating that I would care about kh so now I have to live with it


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## Hanuman (18 Apr 2022)

Easternlethal said:


> Yes I know - but one of the methods, hcl seems the most convenient for me but raises tds as has been pointed out so I just want to understand whether high tds would affect harder to grow plants like pantanal, syns etc
> 
> Yes HK kh is quite low because there's no limestone in this part of the world but I have seryu stones in my tank which can raise kh by as much as 5 (now hovering around 3) and I would like to get it down to 1 or less


I'll be frank but I would highly discourage you to use any sort of strong acids like HCL to reduce KH unless you know exactly what you are doing and understand the chemistry behind it. The use of strong acids to reduce KH is usually left to those with many years of experience and even then it is preferable to use RO than to try to reduce KH in that manner. The likelihood of you messing up one way or another (either with your tank or with yourself) by using acids are high.


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## MichaelJ (18 Apr 2022)

Hanuman said:


> I'll be frank but I would highly discourage you to use any sort of strong acids like HCL to reduce KH unless you know exactly what you are doing and understand the chemistry behind it. The use of strong acids to reduce KH is usually left to those with many years of experience and even then it is preferable to use RO than to try to reduce KH in that matter. The likelihood of you messing up one way or another (either with your tank or with yourself) by using acids are high.


I am 100% with @Hanuman on this!  Stay miles away from messing with hydrochloric acid (HCL) - it's terribly hard to apply the right way and very likely to put your livestock in jeopardy if you get it wrong! - If you can't do RO water or if your tank is too big to make buying distilled water impractical don't worry - you just have be mindful of your choice of plants and might have to dose a bit more fertilizers. That's all!

@Easternlethal  how big is your tank again?

Cheers,
Michael


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## Hanuman (18 Apr 2022)

aquanoobie said:


> Well, looking at your Hong Kong water report you have nothing to worry about. Your local report says 0.5 to 2.4 dKH, average 1.4 dKH.


@Easternlethal If the above is your actual KH I don't even see why you need to reduce your KH. That's plenty low enough to grow virtually 100% of plants in the hobby. Even at 2.4dKH.
*Edit*: sorry just read that you are using Seryu stone. 2 options here. Either you remove them or use RO. Forget the rest. Peat moss will have a very minimal effect, if detectable since the amount of carbonates being dissolved from the stones will largely overcome the buffering capacity of the peat moss.


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## MichaelJ (18 Apr 2022)

Hanuman said:


> @Easternlethal If the above is your actual KH I don't even see why you need to reduce your KH. That's plenty low enough to grow virtually 100% of plants in the hobby. Even at 2.4dKH.
> *Edit*: sorry just read that you are using Seryu stone. 2 options here. Either you remove them or use RO. Forget the rest. Peat moss will have a very minimal effect, if detectable since the amount of carbonates being dissolved from the stones will largely overcome the buffering capacity of the peat moss.


2'ish KH water is perfect if you apply peat moss!  Not a whole lot of buffering capacity there so the peat moss will definitely have an impact driving down both pH as well as the Carbonate hardness (KH) (somewhat) naturally.

Cheers,
Michael


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## Hanuman (18 Apr 2022)

MichaelJ said:


> 2'ish KH water is perfect if you apply peat moss!  Not a whole lot of buffering capacity there so the peat moss will definitely have an impact driving down both pH as well as the Carbonate hardness (KH) naturally (which is what you want).
> 
> Cheers,
> Michael


Yes at 2 dKH and without any carbonate source it's perfectly fine to use peat moss, although not sure of the usefulness, but since he has seryu stone his dKH is probably much higher depending how many stones and how much CO2 he is injecting. I wouldn't be surprised if his dKH was >6-8dKH. Peat moss will do nothing much at those levels and whatever it does it won't be enough to matter. Also something to note, if you use a lot of peat moss you will start coloring the water which is probably not something you want.


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## Yugang (18 Apr 2022)

Hanuman said:


> Yes at 2 dKH and without any carbonate source it's perfectly fine to use peat moss, although not sure of the usefulness, but since he has seryu stone his dKH is probably much higher depending how many stones and how much CO2 he is injecting. I wouldn't be surprised if his dKH was >6-8dKH. Peat moss will do nothing much at those levels and whatever it does it won't be enough to matter. Also something to note, if you use a lot of peat moss you will start coloring the water which is probably not something you want.





Easternlethal said:


> Tank: Dimensions are 160cmX45cmX60cm





Easternlethal said:


> KH is around 1 out of the tap





Easternlethal said:


> Water change 60 - 70% weekly.



With this much WC at KH1, would the stones have that much impact in one week? From what I understand stones are also mostly in the substrate, so less flow around them.


Easternlethal said:


> i used some of it it to prop up substrate



Why not go out hiking @Easternlethal , HK has beautifull rocks everywhere, volcanic origin. Perhaps take some Seryu out and replace with local rock (which has a beautiful color and texture)?


Irrelevant footnote: Geological History and Hong Kong Rocks - Hong Kong Geology. I like my rocks to be 142 mio years old, and that is just what I happen to find around my home.


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## Easternlethal (18 Apr 2022)

Hanuman said:


> @Easternlethal If the above is your actual KH I don't even see why you need to reduce your KH. That's plenty low enough to grow virtually 100% of plants in the hobby. Even at 2.4dKH.
> *Edit*: sorry just read that you are using Seryu stone. 2 options here. Either you remove them or use RO. Forget the rest. Peat moss will have a very minimal effect, if detectable since the amount of carbonates being dissolved from the stones will largely overcome the buffering capacity of the peat moss.



Yes I know I don't need low kh but I'm just trying to see whether it makes some of the more difficult plants I want to grow a bit easier. If it doesn't then I will abandon the idea

Yes I know hcl is difficult, but.. tom barr once said ' you will not get arrested by the fish police for trying'. So it's okay I won't blame anyone if it goes wrong

And Yes I have removed as much seryu as I can. There's just one or two pieces which are being used to prop up the substrate which I can't. My tank is 76 gallons and hovering between 3 and 5 depending on how much co2 I pump in and whether I clean the seryu

For RO it looks like I'll need quite a big unit which I'm not sure I have the space for. 

So I'm thinking of catapa leaves (plentiful supply in our part of the world) and a tiny bit of hcl - just to reduce maybe 50 ppm. 

Anyway I don't really want to derail this thread, which is about lowering tds and I just wanted to understand whether low tds would help plant growth

Really appreciate and grateful for everyone's advice!

I know that many people say dont worry about tds or kh or this or that but in my experience, sooner or later curiosity will always get the better of me and I just have to try something before I will rule it out


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## erwin123 (18 Apr 2022)

Easternlethal said:


> Yes I know I don't need low kh but I'm just trying to see whether it makes some of the more difficult plants I want to grow a bit easier. If it doesn't then I will abandon the idea


What difficult plants are you growing? 
I am also trying to grow difficult plants, but since I am using tap water and a pre-mixed fert, there's only so much I can tweak in those areas. 
Instead, I am focusing on factors I can control like CO2, water circulation, and tank maintenance.


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## plantnoobdude (18 Apr 2022)

Easternlethal said:


> For those who play around with tds, what are the pros and cons in terms of plant health?


TDS it's self doesn't mean much. only if you use full RO can you make a guess at what it is made up of. for example you could have 100ppm TDS from NaCl, or Nh4no3. the "100" number doesn't have much meaning.
I like looking at Tds as it gives you an Idea of nutrients consumption or accumulation.


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## Easternlethal (18 Apr 2022)

plantnoobdude said:


> TDS it's self doesn't mean much. only if you use full RO can you make a guess at what it is made up of. for example you could have 100ppm TDS from NaCl, or Nh4no3. the "100" number doesn't have much meaning.
> I like looking at Tds as it gives you an Idea of nutrients consumption or accumulation


ah i see... right up my street. Sounds like RO is the way to go then.


erwin123 said:


> What difficult plants are you growing?


just the usual suspects - tonina, pantanal, syns, wallichi. some of these I can already grow but its always a bit hit and miss in my current tank


> would the stones have that much impact in one week?


yes they can. seryu stones should come with a warning


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## plantnoobdude (18 Apr 2022)

Easternlethal said:


> ah i see... right up my street. Sounds like RO is the way to go then.


well, even if you go RO if you still have the seiryu stones it will not have much effect.


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## Easternlethal (18 Apr 2022)

i'm not going for 0 - just want to knock off 2 or 3 dkh to get to 1 or 2. am very close already (at 3 to 5). if i see good results then yea I may end up digging them out


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## erwin123 (18 Apr 2022)

Easternlethal said:


> ah i see... right up my street. Sounds like RO is the way to go then.
> 
> just the usual suspects - tonina, pantanal, syns, wallichi. some of these I can already grow but its always a bit hit and miss in my current tank


I have no problems growing them in kH 3-4.


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## Easternlethal (18 Apr 2022)

me too but only with EI/fresh aquasoil/co2


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## aquanoobie (18 Apr 2022)

Easternlethal said:


> ah i see... right up my street. Sounds like RO is the way to go then.





Easternlethal said:


> i'm not going for 0 - just want to knock off 2 or 3 dkh to get to 1 or 2. am very close already (at 3 to 5). if i see good results then yea I may end up digging them out


Why not use the stones since you have them in and they look so nice. Well, you can start changing water using your new RO and not worrying about calcium and KH because the stones will take care of it. 

You only need to add Mg and NPK with trace elements. The RO water changed quantity and timing can be synchronized with testing dKH and TDS.


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