Treating Ro/Di water

Valco213

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I do a weekly water change on my 105 Litre planted community tank with pressurised co2 injection. I have my own Ro/Di unit and change 15 litres each week . My question is what is best to add to the Ro/Di to remineralize. I am aiming for a 3/4 kh and a pH of 6.8.
I have up to now been using Seachem acid and alkaline buffers but cannot understand their dosing instructions. Has anybody got any suggestions . are these the best products to use or are there better alternatives.
The tank is well established and cycled with good water parameters. pH 7 - kh7- Gh7 tested this morning.
Any help would be appreciated
 

Wookii

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The cheapest option to re-mineralise your RO water is to buy the raw salts - namely Calcium Chloride (CaCl2) and Magnesium Sulphate (MgSO4) for the GH, and Potassium Carbonate (K2CO3) for the KH. Have a look at this thread where I was assisted recently in determining the salt quantities for my own RO system: https://www.ukaps.org/forum/threads/gh-kh-ro-reminiralzation-product-help.60556/page-2

If you don't fancy the added complexity, then Salty Shrimp GH/KH+ is an often recommended product.

I will say though, on a high tech CO2 injected tank, you should be looking to do larger water changes, 50 litres+ on your tank, per week.
 

dw1305

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Hi all,
Welcome.
Seachem acid and alkaline buffers but cannot understand their dosing instructions. Has anybody got any suggestions . are these the best products to use or are there better alternatives.
Because you live in Lincoln, and have hard water, you can use your tap water to provide some dGH/dKH from the dissolved "lime scale" (CaCO3). You are only going to need to add a small amount of tap (~10%), so the quality of the tap water is less important.
The cheapest option to re-mineralise your RO water is to buy the raw salts - namely Calcium Chloride (CaCl2) and Magnesium Sulphate (MgSO4) for the GH, and Potassium Carbonate (K2CO3) for the KH. Have a look at this thread where I was assisted recently in determining the salt quantities for my own RO system: https://www.ukaps.org/forum/threads/gh-kh-ro-reminiralzation-product-help.60556/page-2
If you don't want to use tap then @Wookii's is a good suggestion. Another option is <"Oyster Shell Chick Grit">.
I have up to now been using Seachem acid and alkaline buffers but cannot understand their dosing instructions
I have a bit of an issue with the <"clarity of Seachem's product descriptions">, they often seem to <"seek to obscure what their product does">, rather than explain how it works.

cheers Darrel
 

Zeus.

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Another future option will be to tailor your own DIY remineralising salts or clone a commercial one, we should be releasing a new fert calculator which is Excel based which will make the whole DIY calculation side much easier.

Watch this thread ;)
 

DaveWatkin

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The thing I found is to get gh and kh to where you want it and ignore the pH. pH in your premix will be higher as there's no co2 in there, once you put it in the tank with the co2 injection it will stabilise to its normal level.

The pH targeting with alkaline and acid buffers is temporary and designed for getting it into the tank at the right pH but in reality that's not needed. The pH will change slightly at water change but as above will stabilise pretty quickly and a small pH swing will not harm livestock.

I use equalibrium for my gh and alkaline buffer for my kh, no acid buffer used. Will be looking at potential diy solution in the future maybe but for now these are nice and easy for me.
 

Wookii

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Will be looking at potential diy solution in the future maybe but for now these are nice and easy for me.

Definitely worth doing Dave - it's so easy. You can pre-mix concentrated salts in RO/DI water then just dose them into the RO water. I have mine set up so that just 20ml of each is sufficient to remineralise 25 litres of RO.
 

DaveWatkin

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That does sound good. I mix a 120L barrel in my shed that has a circulation pump and heater in which does me 2 weeks of water changes on my two tanks but because of the precipitates from the equilibrium I have to give the barrel a good clean once a month or so which is a pain in the butt logistically. Will check out your post for when my current supply runs out.

The only concern I had was that the seachem mixtures obviously contain various secret compounds, do we lose anything by only remineralising with CaCl2, MgSO4 and K2CO3, will my plants or livestock lose something they require? Not a chemist so may be talking rubbish here haha.
 

Wookii

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The only concern I had was that the seachem mixtures obviously contain various secret compounds, do we lose anything by only remineralising with CaCl2, MgSO4 and K2CO3, will my plants or livestock lose something they require? Not a chemist so may be talking rubbish here haha.

Lol there are no secret compounds in the Seachem mixes Dave - that is precisely what their marketing department want you to think though - they have access only to the same salts the rest of us have. They actually list the physical salts they use on the bottle - all sulphates.



Assuming you are dosing some ferts to your tank, you don't need the micros, and may not need the additional potassium if you have it in a macro mix already. You could just do a copy mix using Potassium Sulphate, Calcium Sulphate and Magnesium Sulphate if you wished, but separate container of Magnesium Sulphate solution and Calcium Chloride solution is what I use as the Calcium Chloride has better solubility.

Seachems Acid Buffer is simply just a carbonate of some sort, so Potassium Carbonate should be a direct single substitute. Again I create a solution of this so a 20ml dose gets my RO water to around 2.5-3KH - keeping everything at 20ml doses makes it easier for my aging brain to remember!!
 
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dw1305

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Hi all,
........do we lose anything by only remineralising with CaCl2, MgSO4 and K2CO3, will my plants or livestock lose something they require?
I'd agree with @Wookii , I think you are good. Your livestock are going to pick up the trace elements they need largely from their food, and your plants from the micro-nutrient solution that you add.
The only concern I had was that the seachem mixtures obviously contain various secret compounds
Yes, we have quite a <"few Seachem threads">.

cheers Darrel
 

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