Reconstituting RO water....?

Naja002

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I finally broke weak and purchased an RO+DI system. I am wanting/needing a Ph of around 6-6.2--Maybe a little higher, maybe a little lower, but right now that's my mark.

I have Barr's GH Booster, so I will be using that, at least until its gone....So I need to understand what I am doing......

I am assuming that I want a KH of about 4, Correct? What about GH?--what am I looking for there?

I've read a ton of threads here and at TPT and APC, but its all kind of gotten jumbled around in my head.

What am I looking for for KH and GH with a PH of 6-6.2 without C02?

TIA
 

Tom Barr

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Most just blend the tap with the RO to hget the KH, then top off any GH with the booster.

Regards,
Tom Barr
 

reiverix

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I collect my RO water in a 5 gallon bucket. Since you must only use cold water with RO units (to protect the RO membrane) I usually drop a small heater in the bucket once it's full to warm the water to tank specs. I also drop in a water pump to circulate the water to speed heating and also to help with mixing the reconstituting powders.

I then add 1.5 tsp of Seachem Equilibrium to increase the GH (you would be adding Barr Booster in your case, probably different amounts also) and .5tsp of plain baking soda to increase the alkalinity (KH). I add a few drops of Seachem Prime just to be sure all chlorine/chloramine is neutralize (since I don't keep up with how long I've been using my carbon stage filters).

Last time I checked, this puts my GH around 6 and my KH around 5, or maybe the other way around. Remember, this RO water is starting out with a GH=0 and KH=0. Anyway, I works well for my plants and fish so I've never felt a need to adjust it. I dunno what my PH is because I use aquasoil and blast Co2 so my in-tank PH is always on the low side, I never test. Back when I did test seems like it was in the 6.x range is all I remember. I don't even have any test tubes left..broke them all and never replaced them. Math/observation is more trustworthy anyway.

The baking soda to increase KH is what's going to affect your PH the most. The less KH you add, the lower your PH will be (since you aren't using Co2 which lowers PH). If the aren't adding Co2, you don't need the high KH to buffer your water against a PH crash.
 

Naja002

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Thanx! I believe I am going to be mixing the RO w/ Tap--which for me is: Ph 8.2, Kh ~14-15, Gh ~17-18. So, from what I understand a 3RO:1T should give me about Kh 4-(3.75) and Gh 4.5 correct? Ph right now is unknown to me, so I'll just have to wait until I actually start mixing.

At a low Ph (~6) and a Kh of 3-4---what is my mark for Gh--(for the plants)?

TIA
 

Naja002

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I don't know--and that's why I am here. If some one could take the time to spell it out for me or provide a good link--that would be Great!

I could probably spend an hr over at SimplyDiscus.com Re-reading, but their site has been down for a while now....The marine sites use high ph water, so that doesn't do me any good.
 

VaughnH

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You need about 2 ppm of KH to get a pH of 6, with no CO2 injection. That is 2 ppm, not 2 dKH. You can check this out by using one of the pH/KH/CO2 calculators, such as on Measuring CO2 levels in a Planted Tank. Just remember that the CO2 in the tank will be around 3 ppm or less with no CO2 injection. So, you play around with entering a pH and a KH and seeing what the ppm of CO2 is. When it hits 3 you are in the right ball park.

Practically speaking, you can't get there by blending the high KH tap water you have with RO/DI water.
 

Naja002

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Practically speaking, you can't get there by blending the high KH tap water you have with RO/DI water.

I agree, but how do I get around the Zero Buffer (Kh) of straight RODI water? Or even can I?

I have been using Seachem's Acid Buffer with this Hard water while deciding/waiting on this RO unit. Acid Buffer lowers pH it converts carbonate alkalinity (KH) into available CO2. So, it will steadily eat away at whatever KH I do have--I don't know that that's a Good thing. In theory I guess, I could continuely add more KH with Baking Soda or Seachem's Alkaline Buffer. Seems like I could work out some kind of receipe to reach the goal.
 

reiverix

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You'd need to mix your RO and tap in a ratio of 150:1 to get your KH to 0.1 which is that 2 ppm.

Using baking soda, Sodium Bicarbonate, adding 1 tsp (tea spoon) (6 grams) to 50 liters of H20 (13.21 gallons) increases the KH to 4.
[http://fins.actwin.com/mirror/Annex/oldfaq-hardness.txt]

You have to divide that KH of 4 by 40 to get 0.1, which means you divide the baking soda dose by 40 as well, so 1/40 of a tsp or...

That means .025 tsp (.15 grams) added to 50 liters (13.21 gallons) will give you a KH of 0.1 (2 ppm) which will put your PH at 6.0
 

Naja002

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Practically speaking, you can't get there by blending the high KH tap water you have with RO/DI water.

I agree, but how do I get around the Zero Buffer (Kh) of straight RODI water? Or even can I?

Having a 0.1 Kh isn't very "safe" is it? Not from what I've learned over time.

I add Humic Acids/Tannins, so will that help bring down the Ph without adding C02?

I'm comfortable enough with a Kh of 2, but I really don't think I want to go below that, correct?
 

reiverix

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Is there a reason you're shooting for a PH of 6-6.2?

You really can't have it both ways without either Co2 or a lot of trouble and fluctuation with adding acids. That's why I'm asking. Wondering how important the PH is to you versus the KH.

What will you be keeping in this water?
 

Naja002

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This is for my A. javanicus. I am seeking to somewhat replicate the Black water pools, streams, rivers, etc of SE Asia. I want the Low Ph and generally very soft water--not just for replication, but for its antiseptic qualities also/mainly. I already add Humic acids and Tannins for their antiseptic qualities. I have been using Seachem's Acid Buffer to keep my Ph between 6-7 and I am already seeing the benefits--I believe: more time will tell. The Ph does get up towards 7, but overall has been staying between 6-6.4. From reading SE Asian Biotope info Ph gets quite low. Ph of 6 is something that I should be able to manage in an aquarium and I can adjust it down further from there with C02 if necessary. But I think Ph 6 will work fine--but its not looking like its going to work at all. Plus I would just like to understand this stuff out of GP.

I use C02 in the Plant Filter and the overflows/returns are under water--except for the overflow from the plant filter to the sump. Its just a water-level overflow and there is mixing of air and water and bubbling at the other end in the sump--So, I am assuming that I am losing some C02 there--if not most or all of it. In the main tank is a Limewood (coralife) airstone, so I am assuming that I am losing all of the C02 there. I also have a large mesh bag of Peat in the canister filter and another one in the sump return prefilter.

Hornwort in the main 40g tank and I just added FISA'a Weeping Moss to a very large rock. In the Plant filter is Hygro Polysperma and Hp 'ceylon', Anachrias and a small amount of Hornwort. All of the plants are doing fine--in the plant filter and main tank, but Gh is around 21 after I add Mg.

Setup is: 40g Tank>30g Plant Filter>40g Sump>back to Tank.

I don't know, but I believe at this point that High 02 levels are important. That is why I have the airstone running. The Hornwort is an Oxygenator, but it is just now getting any real mass to it--Its only been in the main tank for maybe 2 wks. I would like to remove the airstone completely, but I don't want to make too many changes at once--been there done that.

Aside from Ph and Kh---What Gh am I looking for for the Plants?

TIA
 

Tom Barr

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Can you use ADa Aqua soil?

That will get you down to about 5.0-5.4 or so.

I'd not use any KH addition, but you'll need to make a reference KH drop checker, these will work fine for such a set up with no tannins interferences.

KH is used for measuring the CO2 with respect to pH.

It has less of role otherwise........and is not, as near as anyone can tell and argue for, any significant role.

GH is a nutrient mix of Ca/Mg and the anions SO4/Cl so those are useful and required.

Adding MgSO4 and CaCl2 will take care of that.

So if you want, just take into account the GH.
That will give you the lowest pH possible, I doubt you need to worry so much about the pH.

Most fish do not care about that, they do care about purity of the water, NH4,Food, KH.

pH by itself is not that useful of a parameter, so please, do yourself and the fish a favor, do not place so much weight on it when it comes to breeding and fish health, it has much less meaning than most fish folks think.

I do understand they try to give them what is in nature..........but.........that assumes what is in nature is best, clearly that is not the case as all of our argiculture crops and liverstocks are raised much much better in the farms than out in the natural world.

We are much more farmers than we are God creating natural ecosystems.

I think it's much more useful to keep that in mind when culturing fish, plants algae etc.

Regards,
Tom Barr






Regards,
Tom Barr
 
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Naja002

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Thanx Tom,

I understand the gist of what You are saying--especially concerning replication and focusing on one thing like Ph. However, in this case I am seeking the antiseptic qualities of a low Ph environment: the retarding of Bacterial and parasitic growth.

I'm not sure why I would Not be able to use Aquasoil and I will certainly keep it in mind. I may want to go down to a Ph of 5.5, but I really cannot see why that would be necessary. I've been keeping things in the 6-6.4 range and the effect seems positive at this point. But the changing out of the substrate would be very stressful for the A. javanicus (Aquatic Snake) and probably not worth the risk. I should be able to get down to Ph 6 without changing out the substrate--so, I am going to try that first.

My basic game plan right now is (from another Post):


I am initially going to shoot for a Kh of 2 and see where that leaves me with the Ph. I will continue to add the Humic acids and Tannins and see where that leads me with the Ph. Then, depending upon where I am at, I will seriously consider pulling the airstone and adding a C02 reactor to the main tank. If all is well and/or my Ph is too low--then I will Up the Kh to wherever it needs to be. I am not really going to be concerned with the Ph level caused by the C02, but If, after adding C02, I can increase the Kh to say 3 or 4--I will. Problems?

I guess I will shoot for a Gh of 5-6 and just let the plants tell me where it needs to be.

This is all initially for only 2 setups: 1 is only currently about 3g, but the other is ~110g. If I can reach the Sweet spot in the 110g setup--I'll just use water from that for the 3g setup.

Please let me know what them Problems are with my current basic plan.....!!!

The Low Ph and Humic acids are for their on-going antiseptic qualities (cleansing), not just with respect to being initially "Sterile". Hope that makes sense.....

Any Thoughts are Greatly Appreciated!

TIA
 

Tom Barr

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Well, you can if you desire........up to you really.
I do not think you will gain much from that, I do think you woudl gain more from excellent plant growth vs the pH game.

That will reduce parasites, as well as good feeding routines etc.
I've never had parasite issues with Apistos and I've kept them for many years.

Food has a lot to do with it.
I start with the base of the ecosystem: the plants, that's my foundation, then food for the fishes.

Regards,
Tom Barr