GH+KH RO Reminiralzation Product Help.

CJayT

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Soooo, i've been really wracking my brain here about the best product to use to remineralize my ro water. Ideally I wanted to raise both kg and gh. I have a 250ish L aquarium so want a relatively cheap solution. My water is high in nitrates (35-40ishppm) so cutting it with ro isn't really an option and salty shrimp is out of the question due to price. I came across Aqua Source GH and KH buffer and wondered if it would be a good choice even though it is aimed at ponds... Can't seem to find a list of ingredients though?
 

Zeus.

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Aqua Source GH and KH buffer and wondered if it would be a good choice even though it is aimed at ponds... Can't seem to find a list of ingredients though?

Salts are salts , but yes the percentages per mass if elements/compounds would be very helpful :thumbup:

My water is high in nitrates (35-40ishppm) so cutting it with ro isn't really an option

Why not - free NO3

Might be worth having a look at Fert Cal V1.6 beta works out the dkH and dkH form your water report and RO mix and has some salts you can use to get to your targets, if a salt/product isn't on which you would like to use give us a nudge and I will add it ;)
 

zozo

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Epsom is used as fertilizer as a Magnesium source, this will raise GH.

Baking Soda is a Bicarbonate that is used to raise KH.
Pond products sold as KH Plus is actually the very same thing it's Natrium Bicarbonate, but the package doesn't always specify the contents. It also can be bought as a cleaning Agent/Soda, the very same stuff for 3 different applications. In 3 different price ranges, just make sure it is Natrium Bicarbonate and you're good to go for raising KH

Pond and aquarium products soled as GH Plus contain Calcium and Magnesium. If you want to add Calcium only next to the Epsom you can use Calcium carbonate also available as a powder in most pharmacies.

:)
 

dw1305

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Hi all,
best product to use to remineralize my ro water.
Welcome, and look no further, you are in the right place. <"A DIY mix is the way forward">.

As the other have said once an ion is in solution it doesn't matter where it came from, and dry salts are just so much cheaper in the long run.
Might be worth having a look at Fert Cal V1.6 beta works out the dkH and dkH form your water report and RO mix and has some salts you can use to get to your targets
Job done. Another option would be an aragonite calcium carbonate (CaCO3) source, like <"oyster shell chick grit"> or <"cuttle"fish" "bone">.
My water is high in nitrates (35-40ishppm) so cutting it with ro isn't really an option
If you have a hard tap supply you can still cut your RO with tap water, you may only need 10% tap to give you some dGH/dKH.

One of the great advantages of planted tanks is that plants are <"extremely efficient at assimilating all forms of fixed nitrogen">, which means that you don't get a build up of nitrate (NO3-). I like a floating plant in all the tanks, partially because it has <"access to aerial CO2">, and partially because you can use it <"to assess water quality">.

cheers Darrel
 

CJayT

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Epsom is used as fertilizer as a Magnesium source, this will raise GH.

:)

Thanks for all the replies guys. I should have mentioned I intend to EI dose and I also have a fair bit of Seriyu stone in my aquarium. Think I might end up going the DIY route. I've ordered a TDS meter too going to aimfor 120-140. I'm not sure why i'm so afraid of DIY... I've heard people say they're always chasing the ph with bicarb?

Another thing(sorry), when I do a water changes with new r/o water that is remineralised... How do I go about keeping the water chemistry consistent and not end up over concentrating everything?
 

Zeus.

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Another option would be an aragonite calcium carbonate (CaCO3) source, like <"oyster shell chick grit"> or <"cuttle"fish" "bone">.

With the aid of my Fert calculator, I worked out how much uptake of CaCO3 there would be with its salt solubility saturation of 0.015 grams per litre at room temp.

which for my 484 litre tank would be a weekly dose of 7.26grams of CaCO3
upload_2020-4-18_16-32-1.png


So 'if' my maths is correct adding some CaCO3 in excess to any tank should yield the same results of ≈ 0.85°dKH and ≈ 0.81°dGH and if the CaCO3 is in excess it should maintain those minimum values
 

dw1305

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Hi all,
How do I go about keeping the water chemistry consistent and not end up over concentrating everything?
I use a conductivity (TDS) meter to give me a <"datum range where plant growth is acceptable">. Because you will be changing a large volume of water with EI you will probably find that you don't get a large salts build-up.
I've heard people say they're always chasing the ph with bicarb?
It is to do with pH as a measurement, the issue there is that <"pH is a really strange measurement">, and a lot of the conversation is based on the theory that all pH variation is dangerous and must be avoided at all cost. There is a certain amount of truth in this, but what it really means is that large changes in water chemistry aren't good for fish. The "pH stability" idea is to some degree fuelled by some (fairly misleading) advertising <"from the sellers of pH buffers etc">.

Where I would start is that in hard water large changes in water chemistry are required to change pH, but as the water gets softer this relationship breaks down, and by the time you get to pure H2O, pH is a meaningless parameter. Have a look at Diana Walstad's "Star Lake" section in <"TDS and remineralizing.....>.

I didn't know anything about CO2 injection until I joined this forum, but as soon as I found that the people who injected CO2 had a pH drop of one unit when the CO2 is on, followed by a rapid rise of one unit when they turn it off, and their fish were fine. From that I knew that it wasn't pH variation in itself that was the problem. When you add CO2 you haven't changed the alkalinity, you've just changed the <"amount of TIC"> and moved the CO2 ~ HCO3- ~ pH equilibrium towards CO2, and this <"extra dissolved H2CO3 has depressed the pH">.

Even in heavily carbonate buffered situations you can drastically alter the pH just by photosynthesis, in both <"eutrophic enough"> and <"fairly clean water">.

cheers Darrel
 
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Wookii

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Hi all, Welcome, and look no further, you are in the right place. <"A DIY mix is the way forward">.

As the other have said once an ion is in solution it doesn't matter where it came from, and dry salts are just so much cheaper in the long run. Job done.

Hey Darrel,

I’m thinking of moving to RO myself, and fancy trying the James Planted Tank DIY remineralising mix I’ve seen you suggest on a number of threads. I have a couple of questions though:

Firstly, I can write everything I know about chemistry on the back of postage stamp, so can I just check that these are the correct compounds:

Calcium Chloride Dihydrate: https://www.amazon.co.uk/dp/B07TRYH75R/ref=cm_sw_r_cp_api_i_vB.0EbJCEH8AX

Calcium Sulphate Dihydrate: https://www.amazon.co.uk/dp/B07CW1PCKN/ref=cm_sw_r_cp_api_i_nz.0EbEP2DRW0

Magnesium Sulphate Heptahydrate: https://www.amazon.co.uk/dp/B007DGMAIE/ref=cm_sw_r_cp_api_i_JC.0EbMS0JX9J

Potassium Carbonate: I can seem to find this, and have read it can be a little more tricky to keep and handle, so I’m planning to substitute for Potassium Bicarbonate:
https://www.amazon.co.uk/dp/B076634M48/ref=cm_sw_r_cp_api_i_eF.0EbVH9MTEV

Secondly, I plan to automate the generation of the water for the aquarium, so I need to be able to auto-dose premixed liquid salts into the RO tank.

Am I okay to mix the correct ratio of salts with some RO water, as I would for EI fert salts - i.e. there won’t be any strange interactions or other issues with the salts being kept in solution? Would I need to add some Potassium Sorbate if it’s being dosed over a couple of months?
 

Zeus.

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Mucher cheaper on Ebay

Secondly, I plan to automate the generation of the water for the aquarium, so I need to be able to auto-dose premixed liquid salts into the RO tank.

Am I okay to mix the correct ratio of salts with some RO water, as I would for EI fert salts - i.e. there won’t be any strange interactions or other issues with the salts being kept in solution? Would I need to add some Potassium Sorbate if it’s being dosed over a couple of months?

If I was to go down the RO route I would use 'dry salts' to add the minerals back to the RO water when doing WC.
 

Wookii

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Thanks Zeus - I did see the eBay offerings on the Google search - I’m just a little cautious that I’m actually getting what’s being advertised. Have you used that one yourself?


If I was to go down the RO route I would use 'dry salts' to add the minerals back to the RO water when doing WC.

My water changes are daily and fully automated, so dry salts aren’t really an option.
 

Nick72

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I successfully use MgSO4.7H20 (Epsom Salts) for Magnesium, also to raise dGH.

CaSO4.2H20 (Calcium Sulfate Dihydrate / Gypsum) for Calcium, also to raise dGH.

I was using CaCO3 (Calcium Carbonate) for Calcium and additional dKH + dGH, but it does not dissolve well and I found my plants were covered in a dusting of CacO3 that was blocking photosynthesis and creating a anchor point for other organics + algae, so I've gone back to bags of crushed coral for the dKH as released slowly it doesn't have the same dusting issue.
 

Zeus.

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My water changes are daily and fully automated, so dry salts aren’t really an option.

So makes it a little tricky. I was only looking at Seachems Equilibrium the other day/week. they used all sulphates

But then the solubility for CaSO4 isnt great but doable IMO.

so for 100l tank a clone of Seachems Equilibrium
1590996113826.png

1590996458508.png

1590996541692.png


the result above for CaSO4 show it for the dry dose weekly which accounts for the SSL with CaSO4
1590996620227.png

1590996732134.png


So the SSL for CaSO4 is close to its limit !!! maybe a fine tune needed ;)

(Little sneak preview of the 'MTS wizard' in action above in V1.9 - Multiple tanks 🥰)


I was using CaCO3 (Calcium Carbonate) for Calcium and additional dKH + dGH, but it does not dissolve well and I found my plants were covered in a dusting of CacO3 that was blocking photosynthesis and creating a anchor point for other organics + algae, so I've gone back to bags of crushed coral for the dKH as released slowly it doesn't have the same dusting issue.

CaCO3 does have a very low SSL ( see last pic above) so once it is saturated in the tank the dust/powder remains, however using larger particles they easily fall to the substrate level so out of sight for same result without the dusting of plants :thumbup:
 

Wookii

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So makes it a little tricky. I was only looking at Seachems Equilibrium the other day/week. they used all sulphates

But then the solubility for CaSO4 isnt great but doable IMO.

so for 100l tank a clone of Seachems Equilibrium
View attachment 149743
View attachment 149744
View attachment 149745

the result above for CaSO4 show it for the dry dose weekly which accounts for the SSL with CaSO4
View attachment 149746
View attachment 149747

So the SSL for CaSO4 is close to its limit !!! maybe a fine tune needed ;)

(Little sneak preview of the 'MTS wizard' in action above in V1.9 - Multiple tanks 🥰)

Thanks Zeus, that’s awesome. So the Calcium Sulphate is going to be the sticking point.

The James Planted Tank recipe is (ignoring the Kh for now):

0.4g Calcium Chloride Dihydrate
2.0g Calcium Sulphate Dihydrate
2.0g Magnesium Sulphate Heptahydrate
25 litres Water

I’m planning on changing 75 lites per day on the new tank, so I assume I’ll need 3x that, i.e.:

1.2g Calcium Chloride Dihydrate
6.0g Calcium Sulphate Dihydrate
6.0g Magnesium Sulphate Heptahydrate
75 litres Water

So from your spreadsheet, I’d need 3 litres of water to dissolve those 6.0g of Calcium Sulphate - am I reading that correctly? That’s a bit of a blow to morale - I was hoping to get it all done in a couple of hundred ml lol

It’s still doable, but means I probably need to up the size of the salt mixture storage tank to 60 litres+ to get a few weeks worth in there.

Is there another alternative to the Calcium Sulphate? I assume Sodium Chloride can’t just be straight substituted as it’ll add too much Chloride?

PS - that spreadsheet is awesome - you really need to get it integrated on a webpage, you could add some Google advertising then and make a few quid off your efforts!
 

dw1305

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Hi all,
So from your spreadsheet, I’d need 3 litres of water to dissolve those 6.0g of Calcium Sulphate - am I reading that correctly?
You are, but there is a way to increase the solubility of CaSO4.2H2O, which is to cool the solution. Most salts are endothermic and more soluble at higher temperatures, but calcium sulphate is exothermic (heats up when it goes into solution) and cooling it increases the solubility. You would need to store the solution in the fridge to keep the calcium in solution.
Is there another alternative to the Calcium Sulphate?
Yes more calcium chloride (CaCl2.6H2O), it is very soluble, in fact it is so soluble it is really difficult to stop it liquefying.

You aren't particularly interested in the anion, because you are only adding small amounts, calcium nitrate (Ca(NO3)2.4H2O) would be another option.

cheers Darrel
 

Wookii

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Hi all, You are, but there is a way to increase the solubility of CaSO4.2H2O, which is to cool the solution. Most salts are endothermic and more soluble at higher temperatures, but calcium sulphate is exothermic (heats up when it goes into solution) and cooling it increases the solubility. You would need to store the solution in the fridge to keep the calcium in solution.Yes more calcium chloride (CaCl2.6H2O), it is very soluble, in fact it is so soluble it is really difficult to stop it liquefying.

You aren't particularly interested in the anion, because you are only adding small amounts, calcium nitrate (Ca(NO3)2.4H2O) would be another option.

cheers Darrel

Thanks Darrel - refrigeration wouldn’t be practical unfortunately - I barely get enough room to keep my brine shrimp cysts in our fridge! Lol

When you say we aren’t interested in the anion - do you mean that in the case of Calcium Chloride, the chloride element is too small to be of any concern?

So could I swap all of the Calcium Sulphate for a mixture of Calcium Chloride and Calcium Nitrate?
 

dw1305

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Hi all,
When you say we aren’t interested in the anion - do you mean that in the case of Calcium Chloride, the chloride element is too small to be of any concern?
I do.
So could I swap all of the Calcium Sulphate for a mixture of Calcium Chloride and Calcium Nitrate?
You could. All chloride and nitrate salts are soluble, but you may still have problems with the Ca++ ions interacting with the SO4-- (& HCO3-) ions in solution, and <"precipitating out">.

Personally I'm not too bothered in quantifying exactly how much dGH/dKH buffering I have, so I just cut the rain-water in the tanks with a small amount of tap water (about 18 dGH/dKH) to keep it within my <"conductivity datum range">.

I rarely actually measure the conductivity any more, I use the <"state of the snail shells"> to give me a visual clue if the water has got very soft.

cheers Darrel
 

Zeus.

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that spreadsheet is awesome - you really need to get it integrated on a webpage, you could add some Google advertising then and make a few quid off your efforts!

No it will be free for all to use, will be able to use it on only device, NO ADVERTS.


calcium nitrate (Ca(NO3)2.4H2O)

Which was added on request for this reason of boosting the [Ca] when using RO water

calcium chloride (CaCl2.6H2O),

Added on Calculator and you can pick any of the various six Hydrates to use - just have a little 'SSL' to add for each hydrate
 

Wookii

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Hi all, I do.You could. All chloride and nitrate salts are soluble, but you may still have problems with the Ca++ ions interacting with the SO4-- (& HCO3-) ions in solution, and <"precipitating out">.

Personally I'm not too bothered in quantifying exactly how much dGH/dKH buffering I have, so I just cut the rain-water in the tanks with a small amount of tap water (about 18 dGH/dKH) to keep it within my <"conductivity datum range">.

I rarely actually measure the conductivity any more, I use the <"state of the snail shells"> to give me a visual clue if the water has got very soft.

cheers Darrel

Thanks Darrel - so how how much Calcium Nitrate would I need to give the same dGH increase as 6.0g of Calcium Sulphate? And what ppm of Nitrate would that add?

Likewise for Calcium Chloride?

@Zeus. would I be able to use the current version of your calculator to work all the above out?
 

dw1305

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Hi all,
Thanks Darrel - so how how much Calcium Nitrate would I need to give the same dGH increase as 6.0g of Calcium Sulphate? And what ppm of Nitrate would that add?
You just need to work out the relative percentages of calcium (Ca) in each. You do this by adding together the RAMs for each element (Ca = 40, O = 16 etc) to give you the RMM for the compound.

So for Ca(NO3)2.4H2O you have 40 + (14+(3*16))*2 = (40 + 124) = 164 for the Ca(NO3)2 and 4 * ((1+1) + 16) = 72 for the 4H2O giving you an RMM of 164+72 = 236. The percentage of calcium is 40/236 and ~17% Ca.

For CaSO4.2H2O the RMM is 172.2 and you have 40/172.2 = 23.3% Ca, as a ratio that is 1.37, so you multiply 6 * 1.37 = 8.22 g of Ca(NO3)2.4H2O.

The NO3 is the same process, the percentage of NO3 in the calcium nitrate 124/236 = 52.5% and 52.5% of 8.22 = 4.32 g of NO3.
Likewise for Calcium Chloride?
You would need to use the calculation for the <"hexahydrate"> (CaCl2.6H20) the hexahydrate of calcium chloride is the stable form, the dihydrate will absorb atmospheric moisture.

@Zeus. takes out all the hard work/fun from the question, by automating the same process.

cheers Darrel
 
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