How do you remineralize your RO water?

Geoffrey Rea

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Same as @ian_m

Cut with tap water. If I remember right you said your water was liquid rock from the well on the property. If EI dosing you should be able to comprehensively cover all bases on nutrition and have softer water without resorting to remineralising products @DutchMuch
 

ian_m

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Why do you want/need to complicate life by using RO ?

Much much better, much much easier, much much quicker, much much less environmentally damaging to use your tap water. Generally plants and fish do not care about your water parameters, just add dechlorinator to tap water (warm it first ?) and you are good to go. I have very very hard water and have no issues with fish breeding (like rabbits !!!) and plants growing like mad.
 

DutchMuch

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Why do you want/need to complicate life by using RO ?
Few reasons:
The customizability options for water params (a little bit)
my water is liquid rock, or should i say, liquid asteroid, so having RO would allow me to grow a wider variety of plants, like i used to do before i moved here. (Even water lilies have a very hard time growing in this water, water lilies... think of that...)

And in the future if i do sw i will have the RO system on hand :)
 

Zeus.

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Like Dutch I am also tempted to try the RO/tap water mix because of my hard water also for two main reasons.

1. The pH of my tank even with a pH drop over 1.0pH only just makes 7.0pH and DC is yellow so been using Fe DPTA /EDDHA to keep the iron in solution and available to the plants

2. The CEC properties of the AS can be mopped up with hardwater with the excessive ions available which effectively block the exchange properties, so the older the tank a good WC and fert regime is more critical as the buffering of AS is blocked by strong ionic bonding with the excessive ions in hard water.

@dw1305 has mentioned this loss of AS CEC properties with hard water over time.( On mobile phone so links a PITA) but in softer water the extra H+ ions free up the sites on AS and it's CEC keeps working.

Then what I seen at Green Aqua who remin RO water and the success some get with soft water I am tempted to try it.

But all my tanks have hard water and most of the plants look great it's just a few I struggle with and softer water may just enable or make it easier:rolleyes:

Just playing devils advocate OFC ;)
 

DutchMuch

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But all my tanks have hard water and most of the plants look great it's just a few I struggle with and softer water may just enable or make it easier:rolleyes:
i laughed when i read this, due to how ironic it is to my situation:
over the years i have scaped, the only scapes i succeeded in doing relatively well with beautiful thriving plantings were in acidic/soft water! i think it is funny that you are dealing with the opposite, having a hard water tanks in stunning condition as is. I just simply struggle a lot with this as every plant that touches my water, with in my normal high tech setups but just in liquid rock params, all die no matter what eventually. Unless they are aquatic weeds of course haha! very funny
 

alanchown

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I have London tap water, and bought an RO unit last week on a whim, and I can never resist a gizmo. However, although I have only just started reducing my TDS (tank was reading 450, now about 350) since the weekend. It may be my imagination, but my Cardinal Tetras seem to have coloured up enormously. Intending to get to 50:50 RO/Tap over a few weeks.
 

Edvet

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In general i cut 50/50 with tap, sometimes to breed in go 90%.
In my large tank i add 100% RO to combat evaporation, but i do large waterchanges with just regular tapwater ( throw in the garden hose and let it run a few hours)
 

alanchown

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I do a 50% water change (~100L) weekly and also fill straight from hose- so haven't quite figured out how I'm going to get my 50L of RO in without hurting my back!
 

soggybongo

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I use 100% and remineralize using James web site method.
This way I know what is and isn't in my water. Your lucky if you are informed about pre planned water pipework maintenance nevermind emergency pipe maintenance/ repairs where I live and once that work has been done they'll flush with chemicals to clean the pipework. No doubt on the day you carry out a water change. Once bitten twice shy.
 

jaypeecee

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Hi DutchMuch,

I use Tropic Marin Re-Mineral Tropic (RMT) but they also have other re-mineralizers for cichlids, etc. Have been using RMT for a good few years. Tropic Marin's technical support is pretty good too.

JPC
 

dw1305

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Hi all,
In general i cut 50/50 with tap, sometimes to breed in go 90%.
Same for me. I have a good quality hard tap supply and I use rain-water, so the conductivity of the rain-water is a bit more variable than it would be if I used RO.

I don't add a standard amount of tap water, I just keep the tanks within <"a conductivity range">.
I use 100% and remineralize using James web site method.
If I didn't have a hard water supply (~18 dKH/dGH) out of the tap, I would use <"James' Planted Tank"> mix.

I probably would tweak it a little bit by leaving out the calcium sulphate (CaSO4.2H2O) and using potassium bicarbonate (KHCO3), rather than potassium carbonate (K2CO3)*. I would add more potassium bicarbonate (KHCO3) to give a bit more dKH. I'd approx. double the amount of calcium chloride (CaCl2.2H2O).

*I've just looked on a well known auction site and potassium carbonate is widely available and similarly priced to potassium bicarbonate, so you could use either.

The advantage of this is, mainly, that you can buy all the required chemical cheaply and easily as "food grade".

From the <"linked web page">:
dKH: 1dKH = 21.8 ppm HCO3- and dGH = 1dGH = 7.143 ppm Ca++

You can use the <"Rotala Butterfly nutrient calculator"> to check your results.

I won't put in all the calculations, but you would use exactly the same procedure for the other compounds. You probably won't need this, but the process in "the calculation bit" allows you to work out the elements supplied for any compound. It is useful if you have a chemical not included in the <"Rotala Butterfly database">.

The calculation bit
This is calculation for CaCl2.2H2O (so just supplying Ca++ and dGH).

You need to know the RAM of calcium (Ca) etc. I use a <"web periodic table">, so that gives us all the RAM values: Ca = 40, Cl = 35.5, H= 1 & O = 16

rrmXUgcSBfKV8BbNmQdLDH-650-80.jpg


We then need to add these values together to give us the RMM of CaCl.2H2O, so 40 + (35.5*2) + (1*4) + (16*2) = 40 + 71 + 4 + 32 = 147
and the percentage of calcium 40/147 ~ 27% Ca++.

Therefore if we add 10g of CaCl2.2H2O we've added 2.7g of calcium (Ca++)


I'm going to assume we have 100 litres of RO water and that 1dGH is 7 ppm of Ca (just to make the maths. a bit easier to follow).

Then we need to convert from <"grams to ppm">. So 100 litres weighs 100 Kg, there are 1000g in 1 Kg and 100,000 g in 100 litres (easier in scientific notation (powers of 10) 10^2 x 100^3 = 10^5).

If we add 10g of CaCl2.2H2O (2.8g of calcium) to our 100 litres, we've added approx. 28 ppm Ca++. 28/7 = 4 and ~ 4 dGH.

cheers Darrel
 
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dw1305

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Hi all,
There isn't any thing wrong with it, but that one has a lot of sodium (Na) in it.

Companies tell you all sorts of things about being suitable for all tanks, and that fish need sodium for <"osmotic balance">, but I can't get past the point that sodium chloride (NaCl) is the cheapest salt you can buy, and makes a great cheap filler.

My guess would be that every house has some table salt that they could add, if they want to add sodium (Na). I know that table salt contains added iodine (I), and that the anti-caking agent may be sodium hexacyanoferrate (E535), but that isn't going to cause any problems.

I don't know if it is available to you, but <"Seachem Equilibrium"> might be a better option if you want an "off the shelf" product.

Personally I'm not going to buy anything where I could DIY it really easily for <"1/10 of the price">.

cheers Darrel
 

alanchown

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I have an RO unit and in my main 200l tank I cut 50/50 with tap water and all is good. I recently bought a 57l flex which is planted but currently has no fish. My tap water has a TDS of around 350. I thought I may keep Chilli Rasbora. Just for the hell of I thought I'd try using Seachem Equilibrium. I added as per instructions, and this is where I think I have gone wrong, added alkaline and acid buffers. The TDS is over 300, so not much different to tap.
I dose DIY EI from Aquarium Plant food.

Do the buffers add significantly to the TDS? Do I need them?

I know cutting with tap is easier and cheaper, but thought I'd have a play whilst I have no fish.

Alan
 

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